Dstv *****s from me again

I've had this problem with dstv before. Wow I'm back. I called into the centre to ask how much it would cost me to connect my dstv pro rata till my payment date. I spoke with a lady who calculated it for me. I've been paying for my dstv every month. This month when it got disconnected I left it until I could pay again. When I wasted my airtime and called in. A lady gave me an amount of 270 to pay in which I paid in 300. She also changed my payment dates to the second. After calling in to say I've paid I'm surprised to know that I owe amother 345 which no one can tell me the reason or give direct answers. I've really had it with this ****py service. Dstv are thrives. Wasted my time. I could rather download things I watch. When I ask where amounts come from there is no clear answer. We work hard for our money. Don't waste our time. As I type this I'm waiting for a manager to get back to me like I was told would happen when he got off his call that he was in. I'm still waiting. Horrible service