Log into MyAccount
Click on Your Details
Press Change my Direct Debit details in the Your monthly payment details section shown below.
Enter the new Direct Debit details and click I confirm that I'm the account holder and then press Update my details
If this has been successfully completed, you'll receive an email from GoCardless to confirm the new Direct Debit Instruction.
If you have any queries, you can contact the team and they'll be happy to help.