Bad service for Cell C

I have upgraded my account on the 5th of February only to find out later that that particular phone they offered is out of stock. They then phone to offer me a another phone on the 27th of February. When I phoned to find out when the delivery will be I was told the phone is out of stock. I then received my statement and it included a pro rata fee for benefits I received extra for my new contract. What extra benefits? This is really bad service, Cell C. Even your staff says most phones is out of stock? Why then offer me something you don't even have.