Hey there :)
Did open a case lately last year, but get the ticket closed because it's a "known issue" actually.
I just open that thread to get updated on how it goes and when it will be fixed ! :)
The issue : Unable to bind game accounts (in that case, CSGO) to Plays.TV.
The client didn't prompt to confirm the game.
An account already linked which is removed after, can't be added back.
Unfortunately nothing has been done yet. We've been very busy working on the Plays Beta App. However, not being able to bind your CSGO account should not affect the ability to get bookmarks for kills and other events.