Follow option not working correctly in Community Builder

I have two users called user1 and user2 also I have one group name called "Test Group". I have implemented follow button in my application

"user1" was created group name called "Test Group". All the activities feeds will be displaying into "user1" dashboard - "CB Activity module implemented ".
"user2" is not following group "Test Group". Still, all the "Test Group" feeds will be displaying into "user2" dashboard.

If this case - What is the use of "follow" button.

Users will see activity from the groups they've joined in CB GroupJive. They will also see the activity of their connections. So if User A posts in Group A and Group A is a Open group (publicly view-able) then User B will see that activity if they're connected. User B would also see that activity if they joined Group A. The follow feature has nothing to do with that behavior as that's how it's designed.

To best utilize the follow feature you basically need to stop outputting connections activity. To do that set the Asset of your activity stream (if is Activity tab see tab parameters and if is menu item see Activity tab in your menu item) to "user,following", which will show their own activity and the activity of whatever assets they're following.