The issue you're having might be due to the fact that you're trying to log in on the incorrect server. Please make sure to login into your account on the same server where you first created it, with the same linking method. You cannot transfer an account/progress between servers since each of them is considered to be a separate world on its own.
If you are still unable to find your account, please contact us including the following details
Player ID:
Player name:
Original server: