Unwillingly added me to a 24 month contract

<p>My cellphone contract ended with Telkom Mobile last year November 2015, they subsequently moved me onto a month to month with my data and minutes. I then decided to do a name change from my mothers name to my name, since I started working. When I decided to change to prepaid the store told me that I cannot change to prepaid because Telkom moved me onto a 24 month contract when they did a name change, which I did not agree to. &nbsp;I would like to cancel that contract with immediate affect.&nbsp;</p>