One app handle other app's push notification

**# Step to produce issue:**
- I am working with two apps. For this, I create two Firebase project and create firebase app respectively.
- Both apps are installed on my phone.
- Server key is different by project but Fcm token is same.
- Server sends a notification to my one app by Fcm token and Server key.
- If my second app is open then below code of my second app execute
```js
FCM.on(FCMEvent.Notification, (notif) => {
// this code execute
}
```
- I don't know this issue is by server-side or app side. So please guide me, how to solve this issue?