DSTV call center agent give wrong info and the system not working

I called DSTV to confirm,after I send someone to do payment for me and they told her I have credit. And the following month I went to DSTV office they still told me I have credit and I called again to confirm how much I must pay. I was calling DSTV every month still they told me I have credit. On the 13 Feb they disconnected dstv and I called again the following day asking why I'm disconnected, the lady I was talking to told me they made a mistake and dstv was connected again. On the 24 Feb I receive call from dstv told me I'm owing R1200. On the 28 I called asking where that money come from and the lady I was talking to told me it was system mistake. And I have to do payment arrangement. How can I pay for DSTV mistake?