Highly disappointed - Failed upgrade

I've recently been offered an upgrade on my SIM data, only to realise it deactivates my calls and SMSes. I immediately called them and was told they were also not aware of that, hence they did not mention it in the offer. I then cancelled it and reverted to my original package. However, I still got debited the full amount, and I am now being ignored in my emails when I address them. The very same emails we were using to communicate the initial issue, and they were active in responding. Not to mention, I was also charged an admin fee for the upgrade.