Breach of contract. Subscription suspended for bogus "outstanding" fees.

I am a Dstv Premium subscriber but I keep getting disconnected for some "outstanding balance" that came out of nowhere. My account is paid every month by way of debit order. The call centre re-connect the service every second day after a call that could last 57minutes. NONE of the call centre people could inform me where the outstanding balance comes from. Very disappointing as I have been a subscriber for so many years.