Let down -- oversellihg

I received a call from cell c get more and was told to register for their services which i did, I explained to the lady that I needed to use some of the services on monday, when I tried to use the service I was told that I am on trial yet I was told I can use the service the very next day. I called them to cancel and I'm being told to wait 30 days???? This is such a let down.