diff --git a/CHANGELOG.md b/CHANGELOG.md
index ba95844..c7b6db9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,7 +4,6 @@
 
 ### Changed
 - Now requires Craft 4 & PHP 8.0.2
-- `Provider::getConfiguredProvider()` now returns `ProviderInterface` instead of `AbstractProvider`
 
 ### Removed
 - Removed route `oauthclient/authorize/refresh/` use `oauth/authorize/refresh/` instead
diff --git a/src/base/Provider.php b/src/base/Provider.php
index 7d735a5..799d32c 100644
--- a/src/base/Provider.php
+++ b/src/base/Provider.php
@@ -53,7 +53,7 @@ public function getDefaultAuthorizationUrlOptions(): array
      * @inheritDoc
      * @throws ReflectionException
      */
-    public function getConfiguredProvider(): ProviderInterface
+    public function getConfiguredProvider(): AbstractProvider
     {
         if ($this->configuredProvider instanceof AbstractProvider) {
             return $this->configuredProvider;
diff --git a/src/base/ProviderInterface.php b/src/base/ProviderInterface.php
index 4bfc30e..871381e 100644
--- a/src/base/ProviderInterface.php
+++ b/src/base/ProviderInterface.php
@@ -28,9 +28,9 @@ public static function getProviderClass(): string;
 
     /**
      * Gets a concrete League provider instance
-     * @return ProviderInterface
+     * @return AbstractProvider
      */
-    public function getConfiguredProvider(): ProviderInterface;
+    public function getConfiguredProvider(): AbstractProvider;
 
     /**
      * Get the URL used to authorize the token
diff --git a/src/controllers/AppsController.php b/src/controllers/AppsController.php
index d2629fa..cd8ed3a 100644
--- a/src/controllers/AppsController.php
+++ b/src/controllers/AppsController.php
@@ -161,14 +161,13 @@ public function actionSave(): ?\yii\web\Response
 
         // Save it
         if (!Plugin::getInstance()->apps->saveApp($app)) {
-            $session->setError(Craft::t('oauthclient', 'Failed to save app'));
-            // Send the volume back to the template
-            Craft::$app->getUrlManager()->setRouteParams([
+            // TODO: Switch to asModelFailure
+            return $this->asFailure('Failed to save app', [], [
                 'app' => $app
             ]);
-            return null;
         }
 
+        // TODO: Switch to asModuleSuccess
         $session->setNotice(Craft::t('oauthclient', 'App saved'));
         return $this->redirect(UrlHelper::cpUrl('oauthclient/apps/' . $app->handle . ($isNew ? '#info-tab' : '')));
     }
diff --git a/src/models/App.php b/src/models/App.php
index 74e286a..28becf7 100644
--- a/src/models/App.php
+++ b/src/models/App.php
@@ -41,7 +41,7 @@ class App extends Model
     public ?string $provider = null;
     public ?string $name = null;
     public ?string $handle = null;
-    public ?int $clientId = null;
+    public ?string $clientId = null;
     public ?string $clientSecret = null;
     public ?string $urlAuthorize = null;
 
@@ -84,7 +84,7 @@ public function getClientSecret(): string
      */
     public function getUrlAuthorize(): string
     {
-        return \craft\helpers\App::parseEnv($this->urlAuthorize);
+        return \craft\helpers\App::parseEnv($this->urlAuthorize) ?: '';
     }
 
     /**