NO RESPONSE TO UNAUTHORISED DEBITS

I signed a 12 month membership for my family and paid in advance - once off - on my CC. Now I see a monthly debit order going through over a year later on my bank account. I did not authorise this - I do not do debit orders. My son has gone to university and we do not use the gym. I have queried this, been told to contact customer service, been told to send an email, been told it is being referred to head office. 3 weeks later and no response. But today I receive a message to say sorry they are late with the debit order. I urgently require this to be resolved and the unauthorised debits to be refunded. Would someone PLEASE contact me in this regard? Sue Boyce