Price lock mess

I am tired of this call centers that can not help some one, i am on price lock of 749, but they have never deducted the right amount, last month was a R1082. when ever you call them they say the will created a follow up from finance department, i have log 3 now as they say the turn around is 24 Hours, still nothing, I am going to drive to head office make a big scene and make them pay for my petrol as well, this happens when you give them permission for a debit order, never had a issue when i was paying each month, i need a speedy response, as my price lock contract expires in 2 months then i will completely cancel DSTv