Account payments

Flexclub has deducted money from my account even after I informed them a month in advance that I will not be renewing the contract. This is not the first time they take money that doesn't elong to them. 1st month they double deducted and I had to go to the bank and reverse, then they took the same amount of money after couple of hours of reversal. I am not happy that their making my bank statement look like am someone who reverses debt orders. 2nd month they didn't do all these things. 3rd month it was smooth too I think . Then now they took the money that doesn't belong to them even after informing them that the car was collected. I got a nice deal with them but my frustrations is the money they keep deducting, it's time consuming going to the bank for reversals, reversalz don't have a good outlook on my credit score to other service providers and them taking money that doesn't belong to them is making my other commitments not to go as planned .I would like a refund immediately I am not waiting 7 days .I didn't have to on the internet but I would like them to learn a lesson and really remember what they put me through with all these deductions it caused me my peace of mind.