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And then your in a loop. Clearing the browser cache helps sometimes, but that's not the real reason why you are seeing this error.
Have you been reducing the number of global admins recently?
Or perhaps you have been messing around with PIM (Privilidged Access Management)?

Chances are you assigned yourself a load of Roles, because you are important and you need all the different roles.

But when adding to many roles to your account that's when you will see the error above.

So simple solution, lose some roles on your account.