*****ulent debit for a cancelled service - playing games to give my money back

I cancelled my service on 05 October effective 05 November only to be debited again on 05 November. I have now spent over a week begging to get my money refunded, constantly being told to send a valid proof of payment. I have sent a bank statement as they requested and yet still get told to send a 'valid' proof of payment. This is beyond disgraceful, they sitting with my money which they took for a cancelled service and keep playing these silly games when not ghosting me.