MTN non-existent customers Service is horrifying

Our family have been loyal customers of MTN for as many years as there exists cellphone contracts. About a year and a half my mom took out a data contact with a special, 40GB daytime and 40 GB night time for R399, this was on het official contra t stipulated as a 10GB MyData contact, upon asking the representative why 10GB, she said that every month the sy stem adjusts the amount automatically, which actually happened the first couple of months, there after it suddenly did not do that and after some Phone calls and store visits we were informed the sy stem was update and this was a glitch and that they would fix it, the difference in amount that was deducted now was almost R1000 of a pension ers account, which is devastating concidering a pensioners salary. We have had plenty of store visits, hundreds of Phone calls, hundreds of email, just nobody would really help us, they keep passing it to the next person. This has now been going on for more than a year and has placed my parents in an extremely difficult financial situation as MTN Just keep debiting the wrong amount. We are really saddened by this and desperately needs help in resolving this issue.