I need to get my imobiliser PIN reset as I tried to change it to a number I would remember but some how the number was not changed to the one I wanted and the original number does not work either.

I had been told that a dealer could reset to the original number but I have tried to get the dealer to do this on 3 occasions now and have gotten nowhere.

1. Is it possible to reset the PIN to the original number which I have?
2. If the answer to 1 is yes can I do this myself or do I need to find a dealer that knows what they are doing as mine obviously don't.