Hi there, @oaudrey. Is it definitely Fitbit asking you to login? Or is the screen asking for your Apple ID password? Are you asked to login to any other apps? I ask because there is a virus going around that is trying to capture your Apple password.
If the request is appearing to come from Apple, or comes from others apps as well. Then change your password immediately ... power the phone off completely ... then back on.
Please let me know.
Hello again, @oaudrey. I’m afraid I don’t have an answer. But I do have two suggestions.
Either way, please let us know how this issue was resolved.