Frustrated and Disappointed

Vodacom is pathetic , please do not ever take out a contract with them. The worst service provider around. I cancelled my contract 3 months ago and was informed end of August will be the last payment however today I received an invoice from them can you imagine how not impressed I am , sent a mail and still have not received a response. I will never ever want to take out a contract with them again and yet I need an upgrade on my phone...