I have had the same problem. I created a new account because the previous developer left the company, made this new account the main account holder. All working well, then suddently i started failing to log in for no particular reason. Got locked out, tried resetting password and then after a day I got the message about denied access to the account. Now my company's apps are unreachable. I don't believe I have done much that triggered the account lock, apart from trying to login and pay for the developer subscription. No idea how this can be solved since the dev support team is now ghosting me.