Help

I have a very serious problem. Barely a month ago I had taken a subscription to Apple (50 GB of icloud space) and other subscriptions but concerning the storage I terminated and brought it back to the initial free giga (5 GB) and until then Apple continue to debit my account luckily there is nothing on my account. and if I ever reload my bank card they will charge me. I really need help there to stop this! it's urgent