how can i fix my zanussi f/freezer?

sorry-dont know the model but its about 7yrs old&its a chest type only it has front opening doors(freezer left side-fridge right side)its not frost free&i chipped away at the build up with a knife&punctured the freezer section in several places,ive tried to seal all the holes with no nails-seems to have worked but not sure if ive sealed all the holes cos ive switched it back on&its still not freezing-is it possible that i might have lost all the gas?help!!!

steve
April 2008