[MySQL] Impossible to define a permission for a specific user

Issue Symptoms:
When trying to define a permission on a user in the Administration, the action is not saved: the tick is automatically removed.

This behaviour happens in some cases, for instance after removing a user to create the same user but in upper/lowercase.

Workaround:
Log in to your database with the iobeya user.

Then, display the table acl_sid using this request : select * from acl_sid;

Search for the user, you should find the username but in uppercase where the username is in lowercase (or the opposite)

Change the case to the corresponding one, example : update acl_sid set sid="bvarisellaz" where sid="BVARISELLAZ";

Go back to the Administration, and check if it has solved the issue.