Bad service and incompetency

Good day. So Vox advertised data for R179pm. I app**** and recieved a call from their clerk or agent. She never mentioned that the router must be paid off once off and it not covered on the R179pm amount. When they sent me the terms and conditions as well as invoice, I contacted them to say that I don't accept their terms and conditions as I was not informed of the R1479 for the router and the R80 for router. Then requested for my order to be cancelled. I received a reference number. Then the good were delivered and still I made contact to inform them that I need to return their things. Bear in mind, the service was never activated and the goods are still sealed yet am now billed R2448.01. Why am I being for their lack of information and incompetency?