Account always in a mess

Vodacom keeps on phoning to let us know that our account is in arrears, but we paid them in full as requested by phone and sms received. We got confirmation from Vodacom that account has been paid but again today we are told that we are behind in payments. The call center is of no help. My wife requested, seeing the account is in her name, that I am allowed to deal with the account and gave all my details, but every time I phone its an huge issue as they say I am not listed. What gets to me is that I need to get my wife to phone them and then they phone me, but then, buy the next time we have that same issue again. I also feel that the customer contact center staff is rude and its so noisy a person cant make out a word you are saying. Do not even get me started on there internet side of things....I really hope that someone will sort this account out for once and for all and send a confirmation letter so I have proof that this will be the last time and make sure my details are loaded on the account.