diff --git a/sim/api.ts b/sim/api.ts
index 8ae2e2ee..76b4b8db 100644
--- a/sim/api.ts
+++ b/sim/api.ts
@@ -28,9 +28,11 @@ namespace pxsim.hare {
 
 namespace pxsim.unity {
     export function logHello(){
-        window.parent.sendMessage(
-            `SEND_MIXPANEL_EVENT:BtnClickBrowserVideoPlayerClose:VideoId:xx:Timestamp:12`
-          );
+        if (window.parent && typeof window.parent['sendMessage'] === "function") {
+            window.parent['sendMessage'](`SEND_MIXPANEL_EVENT:BtnClickBrowserVideoPlayerClose:VideoId:xx:Timestamp:12`)
+          } else {
+            console.error("Parent function is not available.");
+        }
     }
 }