Att mobile hotspot account locked

I bought a mobile turbo hotspot 2 and when I set it up it told me to create an account/password.  When I tried to log into the website to add data, it told me the password was incorrect and locked me out of my account.  How do I get my account back? My device is past the return date so am I out of my money?  Why did it have me create a password if it wasn’t going to accept it? Thanks in advance if anyone can help me.