Refusing to pay for approved PMBs

Terrible service! I had PMBs activated and not only are Discovery refusing to pay for the approved PMBs services but also reversed a payment that was made 6 months ago. I have consulted with Discovery but all I could be told was "many people are experiencing this problem and we are working to resolve it". THIS IS UNACCEPTABLE! I am paying thousands of rands per month for a service which is costing more than it is worth. I can't afford to cover Discovery's F**K UPS, this is why I pay a monthly fees!