Continuing to debit despite beingInstructed not to

I have instructed since July that you stop my debit order since I am on a sabbatical and not working. You continue to debit me every month, double and triple the amount. I am on a fixed income And have to Keep reversing this. Do you understand the stress you are causing me? And do you understand the impact to my credit record by me continuing to reverse? Why can’t you follow instructions. I am Moving the entire lot. I am done