I had a similar experience. Tried to create an account, but it gave me an error, so I tried again, and it said the account already exists. Clicked on forgot password because I didn't know what the password was, and it said the account was banned for violating the ToS. My theory is that it's because I tried to create an account without linking it to Facebook, so it "accidentally" threw an error, hoping I would create a facebook linked account. Twitter does something similar, where they say a phone number is optional, but they'll immediately lock your new account and say that a phone number is the only way to verify you aren't a bot.

I don't think it's an accident that these high-value tech companies regularly have "errors" when you try to create an account using a method that gives them less access to personal data than other signup methods.