Un authorised deduction

I had contract with them twice, I then informed them I'm no longer interested to continue with them after the end of the last contract. On the last week of August 2026 I received a call that I have an outstanding of R76 and arranged to pay end of August of which I did. To my surprise without my consent they debited R199. 00 on my bank account, this is a day light *******/*****. I need them to refund my account