Hatchback/liftgate Lock problems of the 2003 GMC Envoy

Out back latch door, does not shut properly. You have to slam it, and it feels like it is going to break the glass. It seems like this should be a very big issue because if it fails to stay close like it sometimes does, it could be a very serious issue.

Lift gate, upper molding cracked when opening back hatch window. Poorly designed, contacted GMC basically my problem, even though local GMC dealer has to replace several over the last few years. Also any vibration from the road causes the window and or gate to come unlatched while driving. Spoke to GMC in regards to that and I also checked for recalls. We purchased this vehicle used in 2006 its a 2003 GMC 4x4 slt xl 8-5. 3l.