Vodacom's pathetic service

I was ready to cancel my contract with vodacom after so many years but vodacom manged to convince me other way. The service that I got before getting the correct device was unpleasant. The last guy that I spoke to promised me that he's going to fix the entire thing by lying to me again. The deal he sold me said it has a R500 take a lot voucher. When I call you guys no one knows about the voucher. They all are sending me from pillar to post.