The clixifix support team have no access to your bank details.
An Administrator can change the bank details within your account by selecting Admin > Your Account > Click here to view your payments history (as below)
The Payments page will open with an option to "Create New GoCardless Direct Debit". This will just take a few minutes to complete your new bank details.
You can also contact the gocardless support team on firstname.lastname@example.org or 020 7183 8674 to change the existing details on your Direct Debit. They can be contacted on this number from 9am - 6pm Monday to Friday.