diff --git a/modules/CountlyClass.js b/modules/CountlyClass.js
index 5820a88..64bf65c 100644
--- a/modules/CountlyClass.js
+++ b/modules/CountlyClass.js
@@ -191,6 +191,8 @@ class CountlyClass {
                         log(logLevelEnums.DEBUG, "initialize, No device ID type info from the previous session, falling back to DEVELOPER_SUPPLIED, for event flushing");
                         deviceIdType = DeviceIdTypeInternalEnums.DEVELOPER_SUPPLIED;
                     }
+                    // process async queue before sending events
+                    processAsyncQueue(); 
                     sendEventsForced();
                     // set them back to their initial values
                     this.device_id = undefined;
@@ -1002,6 +1004,8 @@ class CountlyClass {
             // eslint-disable-next-line eqeqeq
             if (this.device_id != newId) {
                 if (!merge) {
+                    // process async queue before sending events
+                    processAsyncQueue(); 
                     // empty event queue
                     sendEventsForced();
                     // end current session
@@ -1254,7 +1258,10 @@ class CountlyClass {
         this.user_details = function (user) {
             log(logLevelEnums.INFO, "user_details, Trying to add user details: ", user);
             if (this.check_consent(featureEnums.USERS)) {
-                sendEventsForced(); // flush events to event queue to prevent a drill issue
+                // process async queue before sending events
+                processAsyncQueue(); 
+                // flush events to event queue to prevent a drill issue
+                sendEventsForced();
                 log(logLevelEnums.INFO, "user_details, flushed the event queue");
                 // truncating user values and custom object key value pairs
                 user.name = truncateSingleValue(user.name, self.maxValueSize, "user_details", log);
@@ -1457,7 +1464,10 @@ class CountlyClass {
             save: function () {
                 log(logLevelEnums.INFO, "[userData] save, Saving changes to user's custom property");
                 if (self.check_consent(featureEnums.USERS)) {
-                    sendEventsForced(); // flush events to event queue to prevent a drill issue
+                    // process async queue before sending events
+                    processAsyncQueue(); 
+                    // flush events to event queue to prevent a drill issue
+                    sendEventsForced(); 
                     log(logLevelEnums.INFO, "user_details, flushed the event queue");
                     toRequestQueue({ user_details: JSON.stringify({ custom: customData }) });
                 }
@@ -1808,6 +1818,8 @@ class CountlyClass {
             this.start_time();
             // end session on unload
             add_event_listener(window, "beforeunload", function () {
+                // process async queue before sending events
+                processAsyncQueue(); 
                 // empty the event queue
                 sendEventsForced();
                 self.end_session();
@@ -3452,7 +3464,6 @@ class CountlyClass {
          * Check and send the events to request queue if there are any, empty the event queue
          */
         function sendEventsForced() {
-            processAsyncQueue(); // process async queue before sending events
             if (eventQueue.length > 0) {
                 log(logLevelEnums.DEBUG, "Flushing events");
                 toRequestQueue({ events: JSON.stringify(eventQueue) });