Incorrect debits

I woke up to a big shock when I realised that they tried to debit my account several times in a single day and because it's not on. 1. The day they should debit and 2. The amount is 3 times what they were supposed to debit, the transactions bounced. This has resulted in my account being overdrawn with R200 worth of fees. I posted on their Social media platform and got no response. I will be cancelling and they will never have my business again.