Sounds, like the tumblers aren't aligned ot aligning properly. Any lock shop should be able to fix it. You can take the lock out and take it to them with the key or take the car in. I don't think dimpled security keys came out until the GTV6s, they are much harder to have duplicated.I've driven the car 5 times now...and have never been able to lock the drivers door. I thought it must require a seperate key for each lock. Anyway today I tried again on my drivers door lock and it works...I had to jiggle the handle a lot though.