Vodacom is being unfair

I have a contract with vodacom which was due for an upgrade. I received a call from a company called rewards company which said they were calling on behalf of vodacom. They offered me an upgrade which I agreed. They sent me the package which I was not happy with. When I called vodacom they said I must call rewards company because they are not able to assist, which I find unfair because I'm contracted to them. Now I'm stuck and don't know what to do because I called the number ********** 666, ********** 111 & ********** 001 which are not going through. Can someone give me assistance please . Vodacom is my service provider, they are supposed to be handling my contract. They contracted a third party to deal with their customers and now we are struggling to get through to those companies. This is totally unacceptable.