Hi ladyharmony and welcome.
I don't personally use Norton so this may not be what you're looking for. But it sounds like your login data might have been corrupted in some way. Perhaps the quickest solution would be to contact Norton customer support.
Norton Help - Product Renewal | Norton Support
I'd use the first link (Norton Product Support - Technical Error) and see if they can help you get unlocked. You'll probably need to provide them with your specific Norton product (NIS, NAV, 360, etc) and license/registration info.