Update:
I went to the Zinio website via my desktop computer and was able to reset my password. I went back to the Surface and was able to open the app and login successfully. Yeah!
I bought a magazine, tried to open it and got the message "An unexpected error has occurred. Please make sure you are logged in to your account, entitled to the magazine you are trying to read and try again. If the problem persists, please contact customer service." Then the app crashed. I tried the process again and got the same error message and crash.
Fortunately the Zinio app on my iPad works so I can read the magazine.