Where are you testing this? It will not work in backend. The reason is user store in backend happens after the state change, which results in the usergroup change being reverted. Same will happen if you use a Field action. You need to be running your tests with frontend. For backend just directly select the usergroup during user edit.

Works perfectly fine in all my tests. There has to be a configuration issue or conflict somewhere then. Please PM backend super administrator login credentials and will take a look.

You have both CBSubs and CB Auto Actions trying to change a users usergroup on subscription state change. They're conflicting with one another. CBSubs usergroup change is happening after CB Auto Actions resulting in CB Auto Actions appearing as if it's doing nothing.

You need to let CBSubs control usergroups or CB Auto Actions instead of trying to use both.

For CB Auto Actions to handle this you'll need 2 actions per plan. 1 to first add the plans usergroup (e.g. Member) with a second usergroup change added to it to remove the Registered usergroup. Then a second action to remove the Member usergroup on plan deactivation. If your plans are all exclusive I'd just go with a Replace Usergroups usage though. I was going to try and help configure this for you, but something is wrong with your backend. I'm constantly stuck in redirect loops.