Unauthorized direct debit.

Hi, I took out a 5 months loan with Capitec around August. The agreement was for them to take their payments every last day of the month, they are my bank so I figured they'd be able to do so without any hustles since they are incharge of my account as my bank. This month they took their money on the17th, without any notification. The money that I had on my account was for paying for my lights and getting food for my mom since I'm going home for Christmas. As I'm speaking I have a balance of R300 on my account, haven't paid for electric. I just hope they don't disconnect it, I have no money to buy food and if by friday they don't return my money that would mean I'm not going home this Christmas. I called them next day of the incident during early hours, they said they will request for the money to be returned. I was just on the phone with one of their agents, what she said was she was going to email the person who assisted me initially for them to call me back. We know that's not going to happen anytime soon, and I need my money urgently. I never agreed to this, Im only getting paid last day of the month like I idvised initially. Please help, I feel very vulnerable right now with no help at all.