2007 Chevy Avalanche Locked Passenger Door

How can I get my passenger door to unlock?
It started when my wife close the door and it didn't catch as it was closed. I told her to hold it (door) and I pressed the locks from the driver side. Once I unlocked the doors again the door would not open. The lock still engages but the door handles will not unlatch the door. I've tried the inside and outside handle of the passenger door with no avail.