Poor client services

I find it difficult to understand why Vodacom agents can call you to sell products but yet, I cannot get any response in cancelling a contract. I am now battling for a week to cancel an expired contract and each and every time I receive an sms telling me that I will receive and e-mail or sms confirming the cancellation which just never happens.................To phone the number provided does not help either...............................AND the local branch in Tzaneen, Limpop, SA will tell you they cannot do it...........it must be done telephonically.