Money taken from my account without my knowledge or permission

I canceled my contract in January 2019, and of course, had to pay a monumental cancellation charge, and then in March, I had R260.43 debited from my account. I have been in touch with customer service and all they can tell me is that it was an "allocation" made for my account. They have not told me what the "allocation" was for? I have a fear that I am going to have rands and rands taken from my account for more "allocations", without any accountability...