Vodacom misled and ignores customer

My husband was called by Vodacom to renew his data contract . He was promised 3gb data and a router for R99. When we received the router, he called them again and was then told its only 1 gig. He cancelled the contract immediately (as it was within the 14 days he could cancel) and Vodacom collected the router. Since then he is charged the R99 every month and its deducted by debit order from my account. He calls them every month to complain with no response.