[thealienwarrior]

For anyone with this problem, as long as you are paying by a visa debit or credit card (so not direct debit) can advise their card issuer they no longer authorise any further payments to a particular retailer.

This can be used in other circumstances too, such as a recurring visa transaction, if the retailer are un-contactable/not responding/refusing to cancel even after advising them you wish to cancel future payments.

It can take a couple of working days to be actioned in full. Just bear in mind, if you do need to make additional payments to anyone once authorisation has been removed, this will need to be by a different means.