Contact accounts@cies.us and provide details about the error message.

Here are a few common error codes and their meanings:
Error 2: Invalid tender type. Your merchant bank account does not support the following credit card type that was submitted.

Error 12: Declined. Check the credit card number and/or expiration date to make sure they were entered correctly. If correct, you must contact your bank and let them know that you want to pay Maestro Meetings in dollars and they should authorize the transaction. This is a common problem with Brazilian banks.

Error 23: Invalid account number. Check credit card number and re-submit.

Error 24: Invalid expiration date. Check and re-submit.

Error 50: Insufficient funds available in account.

Error 150: Issuing bank timed out.

Error 151: Issuing bank unavailable.