Bad service from Rain

I called in March to cancel my subscription. It's well over 2 years since I have had their wifi. They agreed to cancel but will still have to pay end March, I said okay it's fine. I paid. Now on the 30th April they are still deducting. What are they saying it's a month to month contract but when you cancel it it has to take you two months, and on top of that you have to pay bank charges because they are still trying to debit.