In the Administration, you can deactivate and reactivate a user at any time.
1 - Access your team
From your profile (top right), click on “Administration”
2 - Click on "Users"
Then click on "deactivated"
3 - Modify the user
You'll find all your team members.
Click on the 3 dots at the end of the user's line, then on "Reactivate".
The user has now been reactivated.