Signing me up without consent

Signing me up for contracts I did not apply for. I canceled acontract but the guy said to keep itas a month to month data sim, and then later I can cancel if it dont work for me. Well I tried canceling more than a dozen times eithout luck. Then Friday i tried again, but they said it is no longer a month to month. A manager was supposed to phone me but didn't. And now to top it all up they took R50 more from my account