Telkom is the worst service provider

Telkom Mobile services are extremely disappointing. Over the last couple of months I have been having so many issues with Telkom and their ridiculous charges. Telkom has been charging me R200 per failed debit order because they do not take any debit orders from Bidvest bank. I requested that these charges are reversed seeing that I am paying them cash and they refused to. Now Telkom is charging me R500 for data consumption that cannot be explained. I have queried this matter and Telkom has advised that a usage limit of R500 was put on my account without my knowledge. I was never informed about this limit and this limit has now been consumed and I need to pay for it. Every time my data bundle on my Wifi router was depleted I received a message saying "Out of Bundle" and a data bundle needs to be purchased in order to go on the internet. I have tried to understand why this limit was put on my account and why I was not informed or notified about it but no one can explain that to me. Does Telkom really expect customers to pay R500 for data usage that occurred on one day and was not authorized by the account holder. No one in my household I capable of consuming R500's worth of data within in 24 hours. I need an explanation because I refuse to pay that amount when no one can explain this usage to me.