“we couldn’t very your account with that information”

I have played wow on and off for roughly 15 years. my last 3 comps have been macbooks. Every so often I’ll get a message saying “we couldn’t very your account with that information” message but after the 2nd or 3rd try it would work. Now I get the message on the desktop app and mobile app both unable to log into currently. I have verified myself to blizzard, deleted each file and reinstalled them. changed passwords numerous of times. Someone please help with a solution because the GM’s aren’t having much success in the ticket department. That was all what they suggested.

TIA