Please find a suggestion below:
You can create a settings object where you store the maximum number of attempts per service for all users.
Then you can create a new entity between the service and user entity where you cater for an attribute where you can count the attempts. You higher up this number every time a certain user makes use of the service.
Before a certain user would like to use a service, you can check the number of attempts with the value is set as maximum number of attempts for that service (settings object). If it's equal or higher than the maximum number of attempts you return a message, else the user can continue.
Hope this helps.