Frustrating service from Vodacom

I was contacted end of March with an offer to upgrade my contact and explicitly explained to the consultant that my wifi contract was solely for the use in my car as I have wifi at my house and work so the only reason I'd be interested in their unlimited wifi was because it meant the people I travel with would enjoy that perk whilst in my car. We concluded the deal and the consultant said the product would be delivered in two days (the other contract on my sim would automatically be changed). When the delivery arrived, it was a router - which was not what we had agreed upon. I called Vodacom and they said they would send me an SMS confirming when they would come and collect the incorrect product but we are now in May, I'm being debited for a product that I haven't used and whenever I call the call centre, I'm being told that they are going to log my query as urgent but it seems like nothing is being done. Each time I call, I'm told that they are busy with the query but no feedback is provided. I would like urgent assistance on this or can we rather just cancel the wifi contract as it has now become a nightmare for me