(Only firebase expert) Android Firebase Setting Timer on Each Post

I am looking for an expert of Android Firebase platform.

So far, the user is able to create a post and that post is displayed in the MainActivity as a Card View and recyclerview. I am trying to give timer for each post when users create the post so the post will display timer in the Cardview of itself and after 5 minutes it should display "time ended" in a textview inside that cardview.

Problem1:

When I create two posts, timers for these two posts become same.

Goal1:

Each post has to have its own timer value (ex. 3 minutes on post 1, 5 minutes on post 2)

Problem2:

When I click "join" button to go into the post then come back to MainActivity, the timer textview resets. Even though you turn off the application then open it again, it resets.

Goal2: When I come back from other activity, the timer textview must not reset (even when I restart application)

Also, in the [login to view URL], I only enabled post button for my own email address. You can change it to your email.

Android

Project ID: #13159161

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