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OK - sounds like you may have tried pulling the snib up - it's also called the snipper button . The red plastic part of the snib/snipper sometimes can jam it and you need to use a screwdriver to lever it up. Next thing to try is to thump the inner and outer panels with your open palm....not too hard but just enough to 'help' it move if it's a bit stiff. If that fails then it probably means you will need to remove the trim which will be made a lot easier by removing the pass side front bucket seat. You may be able to slide the pass seat fully forwards to allow you to prise the door trim off so you can somehow gain access to the lock otherwise you'll need to pull the trim which ain't the easiest of jobs with the door shut.