Go to "teammembers" in the menu.
A similar list like this will apear.
The TeamTV support user is there for us to help you in case of trouble.
If you click on the 3 dots behind a player you can remove a player/trainer from the team (if you are a trainer).
The data of the player will not be removed from this team. (you want' to keep your statistics).
But afterward the teammember cannot log into this team any more.
Especially when someone progresses to another team this feature will be used.
Probably there will be a special page for this in future because when there is a new season more than one player will have to be moved, especially in youth teams.