Disgusted customer

I'm still waiting for someone to call me back almost 3 weeks later about why DSTV keep changing their debit amounts for my price LOCK. Maybe I am stupid but doesn't price LOCK mean that the price is locked and will not increase/decrease? For 2 months now my debit has not been the agreed R989 pm (as per contract), but on one month it's R1103 and the other month its R1200. What must one do to get a call back? And also this month how much do you feel you'll debit so I can budget according to YOUR needs?