Bad service: ******* into taking new contract

On the 7th February a lady called me to sell me an Alcatel router for 100 gigs, I informed her that I already have a router that I'm still paying for and don't want another one. She checked and told me that my contract has already expired and that I can cancel it anytime. I then agreed to take the new one because I thought that I would just cancelled the old one as it has expired like the lad informed me. I then received the new router on the 14th February, when I called Vodacom on the 15th to cancel the old one, I was informed that it is only expiring in June meaning that the lady **** to me to trick me into taking the contract she was offering. Is this how Vodacom does it's business, after so many years I've been with them I never thought I would get such treatment. I want to return the new router I have just received with immediate effect.