Debit of funds even after 3 months of cancelling my contract

I have been calling planet for the past 3 months to cancel my contract. They keep sending emails stating they are in the process of cancelling it but every month they take money from my account. I went to my bank to stop the debit order but they keep changing the reference. I actually regret signing a contract with them to begin with cause the whole experience was nonsense from the get go. I reversed the transaction yesterday and before midnight they debited my account again. I got an email from belinda stating that my contract is being cancelled and this was on the 2nd of January.