Just to update those who replied to me when I asked for help when my car key wouldn't work after losing my first key.
It turns out that when i had a new E.C.U. fitted last year ( which turned out it didn't really need) they failed to ask me for the spare key to have it recoded. I only found out that the two go hand in hand after doing some research into why the key wouldn't work. They tried to blame me for not taking the key but I explained that how was I supposed to know that the key needed recoding in the first place. Its their job to ask for it surely? Not sure if I can mention the garage concerned but this is just another issue after a catalogue of problems since buying the car. Never again!
Thanks to everyone who took the time to try and help.