When subscription active remove from Joomla Group

Hi there,
I need to show a module only  to users who are logged in but haven't still bought the subscription plan. I set the Access of the module to Registered.

I followed the documentation: a new group called Subscribers, child of Registered; a new access level called Subs with only Subscribers as user group with viewing access.

In the subscription plan, under Joomla Group, When Subscription Active I selected Assign to Joomla Group Subscribers, and remove from Joomla group Registered, as you can see in the screenshot.

However, once the user completes the subscription he's still shown the module even after the subscription is active and he should be only in the Subscribers group.

Am I doing something wrong?
Thanks.