diff --git a/Sources/Clickstream/Dependency/Clickstream/Event/ClickstreamEvent.swift b/Sources/Clickstream/Dependency/Clickstream/Event/ClickstreamEvent.swift
index 09bdf20..605be56 100644
--- a/Sources/Clickstream/Dependency/Clickstream/Event/ClickstreamEvent.swift
+++ b/Sources/Clickstream/Dependency/Clickstream/Event/ClickstreamEvent.swift
@@ -66,7 +66,6 @@ class ClickstreamEvent: AnalyticsPropertiesModel {
 
     func toJson() -> String {
         var event = JsonObject()
-        event["hashCode"] = ""
         event["unique_id"] = uniqueId
         event["event_type"] = eventType
         event["event_id"] = eventId
@@ -94,8 +93,6 @@ class ClickstreamEvent: AnalyticsPropertiesModel {
         event["app_title"] = systemInfo.appTitle
         event["user"] = userAttributes
         event["attributes"] = getAttributeObject(from: attributes)
-        let eventJson = getJsonStringFromObject(jsonObject: event)
-        event["hashCode"] = eventJson.hashCode()
         return getJsonStringFromObject(jsonObject: event)
     }
 
diff --git a/Sources/Clickstream/Network/NetRequest.swift b/Sources/Clickstream/Network/NetRequest.swift
index 48ac73c..4647d73 100644
--- a/Sources/Clickstream/Network/NetRequest.swift
+++ b/Sources/Clickstream/Network/NetRequest.swift
@@ -32,7 +32,8 @@ enum NetRequest {
             URLQueryItem(name: "platform", value: "iOS"),
             URLQueryItem(name: "appId", value: configuration.appId),
             URLQueryItem(name: "compression", value: compression),
-            URLQueryItem(name: "event_bundle_sequence_id", value: String(describing: bundleSequenceId))
+            URLQueryItem(name: "event_bundle_sequence_id", value: String(describing: bundleSequenceId)),
+            URLQueryItem(name: "hashCode", value: requestData.hashCode())
         ]
 
         var request = URLRequest(url: urlComponts.url!, timeoutInterval: 15.0)
diff --git a/Tests/ClickstreamTests/Clickstream/AnalyticsClientTest.swift b/Tests/ClickstreamTests/Clickstream/AnalyticsClientTest.swift
index f21c575..ca779e1 100644
--- a/Tests/ClickstreamTests/Clickstream/AnalyticsClientTest.swift
+++ b/Tests/ClickstreamTests/Clickstream/AnalyticsClientTest.swift
@@ -104,7 +104,7 @@ class AnalyticsClientTest: XCTestCase {
         for i in 0 ..< 501 {
             analyticsClient.addGlobalAttribute("value", forKey: "name\(i)")
         }
-        Thread.sleep(forTimeInterval: 0.1)
+        Thread.sleep(forTimeInterval: 0.2)
         XCTAssertEqual(Event.PresetEvent.CLICKSTREAM_ERROR, eventRecorder.lastSavedEvent?.eventType)
         XCTAssertEqual(Event.ErrorCode.ATTRIBUTE_SIZE_EXCEED, eventRecorder.lastSavedEvent?.attribute(forKey: Event.ReservedAttribute.ERROR_CODE) as! Int)
         let errorValue = eventRecorder.lastSavedEvent?.attribute(forKey: Event.ReservedAttribute.ERROR_MESSAGE) as! String
diff --git a/Tests/ClickstreamTests/Clickstream/AutoRecordEventClientTest.swift b/Tests/ClickstreamTests/Clickstream/AutoRecordEventClientTest.swift
index c2bd9ea..721d7aa 100644
--- a/Tests/ClickstreamTests/Clickstream/AutoRecordEventClientTest.swift
+++ b/Tests/ClickstreamTests/Clickstream/AutoRecordEventClientTest.swift
@@ -139,7 +139,7 @@ class AutoRecordEventClientTest: XCTestCase {
         window.makeKeyAndVisible()
         
         autoRecordEventClient.updateLastScreenStartTimestamp(Date().millisecondsSince1970 - 1_100)
-        
+        Thread.sleep(forTimeInterval: 0.02)
         window.rootViewController = viewControllerB
         window.makeKeyAndVisible()
         XCTAssertTrue(viewControllerA.viewDidAppearCalled)
diff --git a/Tests/ClickstreamTests/Clickstream/EventRecorderTest.swift b/Tests/ClickstreamTests/Clickstream/EventRecorderTest.swift
index 5ea37d9..645e7c2 100644
--- a/Tests/ClickstreamTests/Clickstream/EventRecorderTest.swift
+++ b/Tests/ClickstreamTests/Clickstream/EventRecorderTest.swift
@@ -15,6 +15,7 @@ class EventRecorderTest: XCTestCase {
     let testSuccessEndpoint = "http://localhost:8080/collect"
     let testFailEndpoint = "http://localhost:8080/collect/fail"
     let testSuccessWithDelayEndpoint = "http://localhost:8080/collect/success/delay"
+    let testHashCodeEndpoint = "http://localhost:8080/collect/hashcode"
     var dbUtil: ClickstreamDBProtocol!
     var clickstreamEvent: ClickstreamEvent!
     var eventRecorder: EventRecorder!
@@ -107,7 +108,7 @@ class EventRecorderTest: XCTestCase {
     func testGetEventWithAllAttribute() throws {
         try eventRecorder.save(clickstreamEvent)
         let event = try eventRecorder.getBatchEvent().eventsJson.jsonArray()[0]
-        XCTAssertNotNil(event["hashCode"])
+        XCTAssertNil(event["hashCode"])
         XCTAssertEqual(clickstream.userUniqueId, event["unique_id"] as! String)
         XCTAssertEqual("testEvent", event["event_type"] as! String)
         XCTAssertNotNil(event["event_id"])
@@ -413,34 +414,21 @@ class EventRecorderTest: XCTestCase {
         XCTAssertTrue(eventRecorder.queue.operationCount > 0)
     }
 
-    func testGetEventHashCodeTwice() {
-        let eventJson = clickstreamEvent.toJson()
-        let hashCode1 = eventJson.hashCode()
-        let hashCode2 = eventJson.hashCode()
-        XCTAssertEqual(hashCode1, hashCode2)
-    }
-
-    func testEventModified() throws {
-        let originJson = clickstreamEvent.toJson()
-        let originJsonData = originJson.data(using: .utf8)!
-        var jsonObject = try JSONSerialization.jsonObject(with: originJsonData, options: []) as! [String: Any]
-        let originHashCode = jsonObject["hashCode"] as! String
-        jsonObject["hashCode"] = ""
-        jsonObject["event_type"] = "testEvent1"
-        let jsonWithoutHashCode = clickstreamEvent.getJsonStringFromObject(jsonObject: jsonObject)
-        let computedHashCode = jsonWithoutHashCode.hashCode()
-        XCTAssertNotEqual(originHashCode, computedHashCode)
-    }
-
-    func testEventNotModified() throws {
-        let originJson = clickstreamEvent.toJson()
-        let originJsonData = originJson.data(using: .utf8)!
-        var jsonObject = try JSONSerialization.jsonObject(with: originJsonData, options: []) as! [String: Any]
-        let originHashCode = jsonObject["hashCode"] as! String
-        jsonObject["hashCode"] = ""
-        let jsonWithoutHashCode = clickstreamEvent.getJsonStringFromObject(jsonObject: jsonObject)
-        let computedHashCode = jsonWithoutHashCode.hashCode()
-        XCTAssertEqual(originHashCode, computedHashCode)
+    func testVerifyHashCodeInRequestParameter() {
+        clickstream.configuration.endpoint = testHashCodeEndpoint
+        let eventJson = "[" + clickstreamEvent.toJson() + "]"
+        let eventJsonHashCode = eventJson.hashCode()
+        server["/collect/hashcode"] = { request in
+            let queryParams = request.queryParams
+            // swift lambda for get the hashCode value in queryParams dictionary
+            let hashCodeValue = queryParams.first(where: { $0.0 == "hashCode" })?.1
+            if hashCodeValue == eventJsonHashCode {
+                return .ok(.text("Success"))
+            }
+            return .badRequest(.text("Fail"))
+        }
+        let result = NetRequest.uploadEventWithURLSession(eventsJson: eventJson, configuration: clickstream.configuration, bundleSequenceId: 1)
+        XCTAssertTrue(result)
     }
 }