Poor customer service and wrong debit

Towards the end of February I emailed DStv regarding the promotion that they were running of Compact for R309, the next day one lady foned me and again responded via email to confirm that it was approved, I was then surprised when they sent SMS that say they will debit full amount for Compact for R409. I then foned them three times to try to solve the problem but they seems to be struggling to solve, late on the 25th of March they again sent an SMS stating that they have corrected the problem manually, they minus R100. But on the debit day were they supposed to debit R266 as per their SMS, they then decided to debit R366. I then foned them today the 6th of April asking them to solve the issue but was just told that the problem will be escalated to the relevant department up to so far no one even bother to fone me maybe my problem is useless or they don't respect their clients I don't know. It's very disturbing to see a company like multichoice treating me like this.