Try an old fashioned tac.
Write to the bank with the full details asking for a copy of the contractural terms that they clearly imply you must have signed up to ref. money being deducted without your prior agreement.
Make it clear that the letter is cc to your local newspaper. (Newspapers need stories - it's their life blood and your story is very topical today.)
Your local branch manager DOES have the authority to address the issue and refund you.
If no response then change banks. Be aware though that today no bank has any loyalty to it's customers. They're a money making machine and we are just the material on the conveyor belt.
Don't get mad, get even.