No credit and discount??

Why is my bill 625???? Last month I got a credit and I was promised to get a discount every month like I normally do. Please load a credit for this month immediately and discount every month going forward in order for me to pay R498 like I normally do or else I will cancel and move to another service provider and also list a complaint with ICASA and CPA. This is urgent!!! Why was my discount removed and now I have to ask for it every month???