My passenger side car door does not open, what could cause this? is this common?

You gotta take inside door panel off ,the handles are not pulling lock mechanism enough + it has to be lubed up...

I had exactly the same problem with the passenger door on my 2006 M35X. Was about to attempt taking the panel off when I locked/unlocked the door using the key fob 20-30 times. It may be luck but it finally unlocked.