Charged for no idea...Service blocked and i have paid

I have had my DSTV subscription since 2010, my debit order goes off on the 20th of each month and was on the Compact plus subscription. I downgrade my package in may and in June my debit order went off as usual. on the 04/07/19 my service was blocked and was requested to pay R485 which i paid and now on the 14/07/19 my service was blocked again. Now i'm told to pay a further R900+-..this is so pathetic and and hurts..Spoke to Tasneem one of the managers yesterday and she too could not see what was going on (Said something about someone internally made an error and credited my account and they realized this and my account was then debited with the same amount and that is why my service is blocked). I want this sorted out today!!!!!