Bad business practices

I am a telecom client and have data contract with them. For upgrading my contract with them Selldirect contacted me and the deal they offered didn't suit me and i cancelled it, then we agreed upon a new deal. Two weeks later they sent me a parcel which I thought was the agreed upon deal and i opened the parcel only to find that it's the cancelled deal and now they are forcing me to pay for it. I believe that's how they operate and this is really a bad business practice.