Upgrade done Fruadulently

I received an SMS this morning stating I upgraded. Upgraded from a Top up 50 to MTN 500. I called the call centre this morning and they told me that my line was upgraded yesterday at Cedar Square. I was not near Cedar Square nor did I call MTN to do so. I called MTN a few months ago and they told me I should contact MTN end October to migrate to pre-paid. I do not want a contract with MTN only be on pre-paid. To wake up and find out that I have upgraded is a shock to me.<br> I have logged a ***** report on the internet, call centre said I must get an affidavit so ***** department can look into this. Why must I go trough more trouble to get a problem resolved when I did not create it. Surely you can check your voice recording etc. I can not receive any sms now can only call. I do not want to switch of my phone and start up again. I am too scared. Thus the reason I write this so someone can just assist me and reverse the upgrade and make sure there is not another sim issued with the upgrade. Please migrate package to pre-paid and sort out the ***** on my line. I had billing issues early this year and now this. I have been with MTN for many years and are truly disgusted by this now. <br> <br>