The User can be disabled from the Users tab in the admin dashboard. Go to UserRegistration > Users, and you will see a disable option for each user.
After you click on the disable option for the user, you will see the option to enter the time frame for which you want to disable the user.
You can choose the time period as per your choice in Days / Weeks / Months /Years. Now, the user will not be able to log in to the WP Dashboard or frontend.
If the user wants to log in before this period, the admin will have to enable the user.
