VVM is a ****

I paid a settlement for my Identity account in December 2024. I have been trying to get a paid in full letter since. They keep telling me that the payment is not on their system and they no longer have my account. I have called my bank and they tried to reverse the payment and it said “no authorisation to debit”. So they refuse to give me a paid in full letter or give me back my money . They are big ****mers.