Cotract Cancellation

I phoned Al tech December last year to cancel contract with them.Sel no ***.Vehan convince me to do a upgrade as his service is better than Kimberley. His direct number ***.The phone did not reach me ,his reason being that the right colour is not available. We never discussed a colour. I did request a cancellation .He promised the cancellation will be done and contract being terminated on 25 January. I phoned him 3 more times. The cancellation is still not done but the billing carries on .I pay vie EFT and will not pay this account.H e gave me two references. *** and 581031. Please help me with this.<br> Than you