Front passenger door lock pops back up after locking with key fob. It takes about a dozen attempts before it'll stay locked. This is an 09 XC90 I bought used a few months ago. Any ideas will be appreciated.

I just bought a 2009 XC90 and am very happy so far. No visible signs of any body damage, but about one out of every three times I close the drivers side door it doesn't close all the way. Is this a simple adjustment?