MTN taking money from customers without permission

MTN is actually resorting to *****. It is so frustrating dealing with this company.Two months ago they offered me an online upgrade for 4 of my contracts with a cooling off period. I specifically asked the agent if I would lose data or airtime and she said no. To my astonishment my data was taken. I phoned within the cooling of period and cancelled.They then told me those contacts that I was on is not offered anymore. Why then is there a cooling of period. This month my bill is almost doubled.I came into MTN at East Rand Mall and they said this is online and they cannot assist me. I told them to listen to the voice recordings. They said they don't have access. I would not recommend anyone to give this company business. I also have 2 Vodacom contacts, which I have no issues with. Please be aware of this company