On my 06 civic lx, I can't use the key to turn the lock on the driver side door. There is no key slot on the passenger side. The buttons on the fob work fine to unlock the car and the key starts the car but it won't work when I try it manually, also on the trunk works sometimes and sometimes it doesn't. Any suggestions? Thanks

 

Key is wearing out. The cuts are getting out of tolerance for the pins in the locks. You might want to see the dealer about new keys for the car.