Abuse of Bank information

After not receiving a payment from me, they suspended my subscription on the 6th of February which is fine by me. The horror was that they kept on trying my empty bank account since the 6th of February 4 times a day which charges R8.50 per insufficient funds transaction until the bank phoned me on the 28th of February to inform me that my bank account is overdrawn & owes R848.95 of bank charges. And that's how I found out. I want that money back. I cannot pay for something I didn't use.