Sorry to hear about the experience you had, it was clearly difficult and upsetting.
How to complain depends on what type of bailiff they are. They are usually what we call a certified bailiff. I have enclosed below further details about complaining about a bailiff. The information from the CAB is very helpful.
Otherwise, you can check whether they are a certified bailiff on the certified bailiff register. If they said they were a high court enforcement officer. contact the court that sent them - a county court bailiff, family court bailiff or a civilian enforcement officer then contact the local Court. There is a form you can use to send to the Court who sent them. I have attached the link here
As for a phone call, I can't take one right now. I can't take a phone call at the moment. You don't have to have a phone call. Customer Services should be able to arrange a refund, I'm afraid we have nothing to do with charges and billing.
I trust that the above is helpful. They should have left some paperwork behind which will help you with the complaint. If you have any other questions, let me know.