It is possible that you created two accounts in the system. You have to log in using the same account you used to pay for the course. If you can't remember the username or password you used when you paid, we can help you recover them. Do not create a new account. Your payment will not be associated with the new account.
If you purchased multi-term access last term, then you just need to apply your credit. Just be sure sure to use the same login as you did last term.
If the suggestions above don’t help, please contact tech support with your transaction or receipt ID.