diff --git a/composer.json b/composer.json
index 8fef9dd..c8a0056 100644
--- a/composer.json
+++ b/composer.json
@@ -42,5 +42,9 @@
         "kriswallsmith/buzz" : "^1.1",
         "nyholm/psr7" : "^1.3",
         "silverstripe/framework" : "^4"
+    },
+    "require-dev": {
+        "phpunit/phpunit": "^9.5",
+        "friendsofphp/php-cs-fixer": "^3"
     }
 }
diff --git a/src/Connector/Event.php b/src/Connector/Event.php
index 6fea3d2..13d6bfc 100644
--- a/src/Connector/Event.php
+++ b/src/Connector/Event.php
@@ -17,7 +17,7 @@ class Event extends Base
     /**
      * @param string $begin an RFC 2822 formatted UTC datetime OR empty string for no begin datetime
      * @param string $event_filter see https://documentation.mailgun.com/en/latest/api-events.html#event-types can also be a filter expression e.g "failed OR rejected"
-     * @param boolean $resubmit whether to resubmit events if possible
+     * @param array $extra_params extra parameters for API request
      * @return array
      */
     public function pollEvents($begin = null, $event_filter = "", $extra_params = array())
diff --git a/src/Connector/Message.php b/src/Connector/Message.php
index 973f522..3ce2191 100644
--- a/src/Connector/Message.php
+++ b/src/Connector/Message.php
@@ -4,6 +4,7 @@
 use Mailgun\Mailgun;
 use NSWDPC\Messaging\Mailgun\Log;
 use NSWDPC\Messaging\Mailgun\Connector\Event as EventConnector;
+use Mailgun\Model\Message\SendResponse;
 use Mailgun\Model\Message\ShowResponse;
 use NSWDPC\Messaging\Mailgun\SendJob;
 use NSWDPC\Messaging\Mailgun\MailgunEvent;
@@ -84,7 +85,6 @@ public function getMime(MailgunEvent $event)
      * See: http://mailgun-documentation.readthedocs.io/en/latest/api-sending.html#sending
      * @return SendResponse|QueuedJobDescriptor|null
      * @param array $parameters an array of parameters for the Mailgun API
-     * @param string $in a strtotime value added to 'now' being the time that the message will be sent via a queued job, if enabled
      */
     public function send($parameters)
     {
@@ -127,7 +127,7 @@ public function send($parameters)
     protected function sendMessage(array $parameters) {
 
         /**
-         * @var Mailgun\Mailgun
+         * @var \Mailgun\Mailgun
          */
         $client = $this->getClient();
         /**
@@ -245,8 +245,7 @@ public function isDelivered(MailgunEvent $event, $cleanup = true)
             'recipient' => $event->Recipient,// match against the recipient of the event
         ];
 
-        // calling pollEvents will store  matching local MailgunEvent record(s)
-        $events = $connector->pollEvents($begin, $event_filter, $resubmit, $extra_params);
+        $events = $connector->pollEvents($begin, $event_filter, $extra_params);
 
         $is_delivered = !empty($events);
         return $is_delivered;
@@ -255,7 +254,7 @@ public function isDelivered(MailgunEvent $event, $cleanup = true)
     /**
      * Trim < and > from message id
      * @return string
-     * @param string
+     * @param string $message_id
      */
     public static function cleanMessageId($message_id)
     {
@@ -356,7 +355,6 @@ public function getVariables() {
 
     /**
      * Based on options set in {@link NSWDPC\Messaging\Mailgun\MailgunEmail} set Mailgun options, params, headers and variables
-     * @param NSWDPC\Messaging\Mailgun\MailgunEmail $email
      * @param array $parameters
      */
     protected function addCustomParameters(&$parameters)
diff --git a/src/Connector/Webhook.php b/src/Connector/Webhook.php
index 32a3796..ab53fd5 100644
--- a/src/Connector/Webhook.php
+++ b/src/Connector/Webhook.php
@@ -15,7 +15,7 @@ class Webhook extends Base {
     /**
      * verify signature
      * @return true returns true if signature is valid
-     * @param array
+     * @param array $signature
      */
     public function verify_signature($signature)
     {
@@ -27,7 +27,7 @@ public function verify_signature($signature)
 
     /**
      * Sign the token based on timestamp and signature in request
-     * @param array
+     * @param array $signature
      */
     public function sign_token($signature) {
         $webhook_signing_key = $this->getWebhookSigningKey();
@@ -39,7 +39,7 @@ public function sign_token($signature) {
 
     /**
      * Based on Mailgun docs, determine if the signature is correct
-     * @param array
+     * @param array $signature
      */
     public function is_valid_signature($signature) {
         return isset($signature['timestamp'])
diff --git a/src/Controllers/MailgunModelAdmin.php b/src/Controllers/MailgunModelAdmin.php
index 41a9868..e92f16b 100644
--- a/src/Controllers/MailgunModelAdmin.php
+++ b/src/Controllers/MailgunModelAdmin.php
@@ -32,14 +32,16 @@ public function getEditForm($id = null, $fields = null)
         $form = parent::getEditForm($id, $fields);
 
         $grid = $form->Fields()->dataFieldByName($this->sanitiseClassName($this->modelClass));
-        $config = $grid->getConfig();
+        if($grid instanceof GridField) {
+            $config = $grid->getConfig();
 
-        $config->removeComponentsByType(GridFieldAddNewButton::class);
-        $config->removeComponentsByType(GridFieldPrintButton::class);
+            $config->removeComponentsByType(GridFieldAddNewButton::class);
+            $config->removeComponentsByType(GridFieldPrintButton::class);
 
-        if(! Permission::check( MailgunEvent::PERMISSIONS_DELETE, 'any', Member::currentUser()) ) {
-            $config->removeComponentsByType(GridFieldEditButton::class);
-            $config->removeComponentsByType(GridFieldDeleteAction::class);
+            if(! Permission::check( MailgunEvent::PERMISSIONS_DELETE, 'any', Member::currentUser()) ) {
+                $config->removeComponentsByType(GridFieldEditButton::class);
+                $config->removeComponentsByType(GridFieldDeleteAction::class);
+            }
         }
 
         return $form;
diff --git a/src/Email/MailgunEmail.php b/src/Email/MailgunEmail.php
index 2782a13..4e3ff0b 100644
--- a/src/Email/MailgunEmail.php
+++ b/src/Email/MailgunEmail.php
@@ -37,7 +37,7 @@ class MailgunEmail extends Email {
 
     /**
      * Retrieve the connector instance
-     * @return NSWDPC\Messaging\Mailgun\Connector\Message
+     * @return \NSWDPC\Messaging\Mailgun\Connector\Message
      * @deprecated
      */
     public function getConnector() : Message {
diff --git a/src/Email/MailgunMailer.php b/src/Email/MailgunMailer.php
index 9a6251f..9cb862b 100644
--- a/src/Email/MailgunMailer.php
+++ b/src/Email/MailgunMailer.php
@@ -60,7 +60,7 @@ public function getAlwaysFrom() {
     /**
      * Retrieve and set custom parameters on the API connector
      * @param MailgunEmail $email
-     * @param MessageConnector connector instance for this send attempt
+     * @param MessageConnector $connector instance for this send attempt
      * @return MessageConnector
      */
     protected function assignCustomParameters(MailgunEmail &$email, MessageConnector &$connector) : MessageConnector {
@@ -77,7 +77,7 @@ protected function assignCustomParameters(MailgunEmail &$email, MessageConnector
     }
 
     /**
-     * @param Email
+     * @param Email $email
      * @returns mixed
      */
     public function send($email)
@@ -103,7 +103,7 @@ public function send($email)
             } else {
                 throw new \Exception("Tried to send, expected a SendResponse or a QueuedJobDescriptor but got type=" . gettype($response));
             }
-        } catch (Exception $e) {
+        } catch (\Exception $e) {
             Log::log('Mailgun-Sync / Mailgun error: ' . $e->getMessage(), \Psr\Log\LogLevel::NOTICE);
         }
         return false;
@@ -212,11 +212,9 @@ public function prepareParameters(Email $email, MessageConnector $connector) : a
         // if Cc and Bcc have been provided
         if (isset($headers['Cc'])) {
             $parameters['cc'] = $headers['Cc'];
-            unset($parameters['h:Cc']);//avoid double Cc header
         }
         if (isset($headers['Bcc'])) {
             $parameters['bcc'] = $headers['Bcc'];
-            unset($parameters['h:Bcc']);//avoid sending double Bcc header
         }
 
         // Provide Mailgun the Attachments. Keys are 'fileContent' (the bytes) and filename (the file name)
@@ -241,7 +239,7 @@ public function prepareParameters(Email $email, MessageConnector $connector) : a
 
     /**
      * Given {@link \SilverStripe\Control\Email\Email} configuration, apply relevant values
-     * @param array
+     * @param array $parameters
      */
     public function assignDefaultParameters(&$parameters) {
 
@@ -348,7 +346,7 @@ protected function prepareHeaders(Swift_Mime_SimpleHeaderSet $header_set)
      *		 'contents' => $data,
      *		 'filename' => $filename,
      *		 'mimetype' => $mimetype,
-     * @param array $attachements Each value is a {@link Swift_Attachment}
+     * @param array $attachments Each value is a {@link Swift_Attachment}
      */
     protected function prepareAttachments(array $attachments)
     {
diff --git a/src/Jobs/SendJob.php b/src/Jobs/SendJob.php
index bad43ac..f51d5a5 100644
--- a/src/Jobs/SendJob.php
+++ b/src/Jobs/SendJob.php
@@ -62,7 +62,7 @@ public function getSignature()
         // these simple message params
         $parts = ['to','from','cc','bcc','subject'];
         foreach($parts as $part) {
-            $params[ $part ] = isset($parameters[ $part ])  ? $parameters[ $part ] :  '';
+            $params[ $part ] = isset($this->parameters[ $part ])  ? $this->parameters[ $part ] :  '';
         }
         // at this time
         $params['sendtime'] = microtime(true);
@@ -71,8 +71,8 @@ public function getSignature()
 
     /**
      * Create the job
-     * @param string domain DEPRECATED
-     * @param array parameters for Mailgun API
+     * @param string $domain DEPRECATED
+     * @param array $parameters for Mailgun API
      */
     public function __construct($domain = "", $parameters = [])
     {
diff --git a/src/Models/MailgunEvent.php b/src/Models/MailgunEvent.php
index 9234afe..d67fa53 100644
--- a/src/Models/MailgunEvent.php
+++ b/src/Models/MailgunEvent.php
@@ -262,7 +262,7 @@ public function getCmsFields()
 
     /**
      * Events that are sibling to this event (sharing the smae MessageId)
-     * @return DataList
+     * @return \SilverStripe\ORM\DataList
      */
     public function getSiblingEvents()
     {
@@ -428,7 +428,7 @@ private function saveDeliveryStatus(array $delivery_status)
 
     /**
      * Given a Mailgun\Model\Event\Event, store if possible
-     * @param Mailgun\Model\Event\Event $event
+     * @param MailgunEventModel $event
      * @return MailgunEvent|boolean
      */
     public function storeEvent(MailgunEventModel $event)
diff --git a/src/ORM/FieldType/DBLongText.php b/src/ORM/FieldType/DBLongText.php
index fab0426..d9be872 100644
--- a/src/ORM/FieldType/DBLongText.php
+++ b/src/ORM/FieldType/DBLongText.php
@@ -34,7 +34,7 @@ public function requireField()
             $charset = Config::inst()->get(MySQLDatabase::class, 'charset');
             $collation = Config::inst()->get(MySQLDatabase::class, 'collation');
             $values = "longtext character set {$charset} collate {$collation}";
-            DB::require_field($this->tableName, $this->name, $values, $this->default);
+            DB::require_field($this->tableName, $this->name, $values);
         } else {
             // different manager e.g SQLite3 TEXT = 2^31 - 1 length
             parent::requireField();
diff --git a/tests/MailgunSyncTest.php b/tests/MailgunSyncTest.php
index b829271..fbdf929 100644
--- a/tests/MailgunSyncTest.php
+++ b/tests/MailgunSyncTest.php
@@ -47,12 +47,11 @@ class MailgunSyncTest extends SapphireTest
                             . "<p>consulting support conversation advertisements policy promotional request.</p>"
                             . "<p>Option purpose programming</p>";
 
-    public function setUp()
+    public function setUp() : void
     {
         parent::setUp();
         // Avoid using TestMailer for this test
-        $this->mailer = MailgunMailer::create();
-        Injector::inst()->registerService($this->mailer, Mailer::class);
+        Injector::inst()->registerService(new MailgunMailer(), Mailer::class);
         // use MailgunEmail
         Injector::inst()->registerService(MailgunEmail::create(), Email::class);
 
@@ -61,10 +60,10 @@ public function setUp()
 
         // modify some config values for tests
         // never send via a job
-        Config::inst()->update(Base::class, 'api_domain', $this->test_api_domain);
-        Config::inst()->update(Base::class, 'api_key', $this->test_api_key);
-        Config::inst()->update(Base::class, 'send_via_job', 'no');
-        Config::inst()->update(Base::class, 'api_testmode', true);
+        Config::modify()->set(Base::class, 'api_domain', $this->test_api_domain);
+        Config::modify()->set(Base::class, 'api_key', $this->test_api_key);
+        Config::modify()->set(Base::class, 'send_via_job', 'no');
+        Config::modify()->set(Base::class, 'api_testmode', true);
     }
 
     /**
@@ -73,11 +72,11 @@ public function setUp()
     public function testApiDomain() {
         $currentValue = Config::inst()->get(Base::class, 'api_domain');
         $value = "testing.example.org";
-        Config::inst()->update(Base::class, 'api_domain', $value);
+        Config::modify()->set(Base::class, 'api_domain', $value);
         $connector = MessageConnector::create();
         $result = $connector->getApiDomain();
         $this->assertEquals($value, $result);
-        Config::inst()->update(Base::class, 'api_domain', $currentValue);
+        Config::modify()->set(Base::class, 'api_domain', $currentValue);
     }
 
     /**
@@ -86,7 +85,7 @@ public function testApiDomain() {
     public function testApiEndpoint() {
 
         $value = 'API_ENDPOINT_EU';
-        Config::inst()->update(Base::class, 'api_endpoint_region', $value);
+        Config::modify()->set(Base::class, 'api_endpoint_region', $value);
         $connector = MessageConnector::create();
         $domains = $connector->getClient();
         // assert that the expected URL value is what was set on the client
@@ -94,7 +93,7 @@ public function testApiEndpoint() {
 
         // switch to default region
         $value = '';
-        Config::inst()->update(Base::class, 'api_endpoint_region', $value);
+        Config::modify()->set(Base::class, 'api_endpoint_region', $value);
         $connector = MessageConnector::create();
         $domains = $connector->getClient();
         // when no value is set, the default region URL is used
@@ -216,7 +215,7 @@ public function testMailerDelivery($subject = "test_mailer_delivery")
      * Test delivery via a Job
      */
     public function testJobMailerDelivery() {
-        Config::inst()->update(Base::class, 'send_via_job', 'yes');
+        Config::modify()->set(Base::class, 'send_via_job', 'yes');
         // send message
         $subject = "test_mailer_delivery_job";
         $sendData = $this->testMailerDelivery($subject);
@@ -230,7 +229,7 @@ public function testJobMailerDelivery() {
     public function testAlwaysFrom() {
 
         $alwaysFromEmail = 'alwaysfrom@example.com';
-        Config::inst()->update(MailgunMailer::class, 'always_from', $alwaysFromEmail);
+        Config::modify()->set(MailgunMailer::class, 'always_from', $alwaysFromEmail);
 
         $to_address = $this->config()->get('to_address');
         $to_name = $this->config()->get('to_name');
@@ -273,7 +272,7 @@ public function testAlwaysFrom() {
     public function testAPIDelivery()
     {
 
-        Config::inst()->update(Base::class, 'send_via_job', 'no');
+        Config::modify()->set(Base::class, 'send_via_job', 'no');
 
         $connector = MessageConnector::create();
         $to = $to_address = $this->config()->get('to_address');
@@ -315,7 +314,7 @@ public function testAPIDelivery()
         $this->assertEquals(TestMessage::MSG_ID, $response->getId());
         $sendData = TestMessage::getSendData();
 
-        $this->arrayHasKey('parameters', $sendData);
+        $this->assertArrayHasKey('parameters', $sendData);
 
         foreach(['o:testmode','o:tag','from','to','subject','text','html'] as $key) {
             $this->assertEquals($parameters[ $key ], $sendData['parameters'][ $key ]);
@@ -333,10 +332,10 @@ public function testSendWithDefaultConfiguration() {
         $overrideBcc = 'bccallemailsto@example.com';
         $overrideBccName = 'bcc person';
 
-        Config::inst()->update(Email::class, 'send_all_emails_to', $overrideTo);
-        Config::inst()->update(Email::class, 'send_all_emails_from', $overrideFrom);
-        Config::inst()->update(Email::class, 'cc_all_emails_to', $overrideCc);
-        Config::inst()->update(Email::class, 'bcc_all_emails_to', [ $overrideBcc => $overrideBccName ]);
+        Config::modify()->set(Email::class, 'send_all_emails_to', $overrideTo);
+        Config::modify()->set(Email::class, 'send_all_emails_from', $overrideFrom);
+        Config::modify()->set(Email::class, 'cc_all_emails_to', $overrideCc);
+        Config::modify()->set(Email::class, 'bcc_all_emails_to', [ $overrideBcc => $overrideBccName ]);
 
         $to_address = $this->config()->get('to_address');
         $to_name = $this->config()->get('to_name');
@@ -367,7 +366,7 @@ public function testSendWithDefaultConfiguration() {
         $sendData = TestMessage::getSendData();
 
         foreach(['domain','parameters','sentVia','client','in'] as $key) {
-            $this->arrayHasKey($key, $sendData);
+            $this->assertArrayHasKey($key, $sendData);
         }
 
         $this->assertEquals($this->test_api_domain, $sendData['domain']);
@@ -429,16 +428,16 @@ public function testAttachmentDelivery() {
 
         $sendData = TestMessage::getSendData();
 
-        $this->arrayHasKey('parameters', $sendData);
-        $this->arrayHasKey('attachment', $sendData['parameters']);
+        $this->assertArrayHasKey('parameters', $sendData);
+        $this->assertArrayHasKey('attachment', $sendData['parameters']);
         $attachments = $sendData['parameters']['attachment'];
 
         $f = 1;
         $this->assertEquals(count($files), count($attachments));
         foreach($attachments as $attachment) {
-            $this->arrayHasKey( 'filename', $attachment );
-            $this->arrayHasKey( 'mimetype', $attachment );
-            $this->arrayHasKey( 'fileContent', $attachment );
+            $this->assertArrayHasKey( 'filename', $attachment );
+            $this->assertArrayHasKey( 'mimetype', $attachment );
+            $this->assertArrayHasKey( 'fileContent', $attachment );
             foreach($files as $file => $mimetype) {
                 if($file == $attachment['filename']) {
                     $this->assertEquals($mimetype, $attachment['mimetype']);
diff --git a/tests/WebhookTest.php b/tests/WebhookTest.php
index 1c02b35..46a0e80 100644
--- a/tests/WebhookTest.php
+++ b/tests/WebhookTest.php
@@ -21,11 +21,11 @@ class WebhookTest extends FunctionalTest
 
     protected $usesDatabase = true;
 
-    public function setUp() {
+    public function setUp() : void {
         parent::setUp();
-        Config::inst()->set(Base::class, 'webhook_filter_variable', $this->webhook_filter_variable);
-        Config::inst()->set(Base::class, 'webhook_previous_filter_variable', $this->webhook_previous_filter_variable);
-        Config::inst()->set(Base::class, 'webhooks_enabled', true);
+        Config::modify()->set(Base::class, 'webhook_filter_variable', $this->webhook_filter_variable);
+        Config::modify()->set(Base::class, 'webhook_previous_filter_variable', $this->webhook_previous_filter_variable);
+        Config::modify()->set(Base::class, 'webhooks_enabled', true);
     }
 
     /**
@@ -51,10 +51,10 @@ protected function getConnector() {
 
     /**
      * Set a signing key in Configuration
-     * @param string
+     * @param string $signing_key
      */
     protected function setSigningKey($signing_key) {
-        Config::inst()->set(Base::class, 'webhook_signing_key', $signing_key);
+        Config::modify()->set(Base::class, 'webhook_signing_key', $signing_key);
     }
 
     /**
@@ -131,8 +131,8 @@ protected function sendWebhookRequest($type) {
 
         // remove webhook variable and test
         unset( $data['event-data']['user-variables']['wfv'] );
-        Config::inst()->set(Base::class, 'webhook_filter_variable', '');
-        Config::inst()->set(Base::class, 'webhook_previous_filter_variable', '');
+        Config::modify()->set(Base::class, 'webhook_filter_variable', '');
+        Config::modify()->set(Base::class, 'webhook_previous_filter_variable', '');
 
         // change the signing key in config, it should fail now
         $signing_key = "YOU_SHALL_NOT_PASS";