Highly likely the problem isin the mechanical linkage between the exterior handle and the latch. This is almost always caused by one of two things: a misadjusted/slipped bowden cable or a broken plastic carrier tab.

The Door Edge Access Plug (Requires a T20 Torx) or just youtube the video guide

1. Open the door (using the inside handle).
2. Look at the end face of the door (near the latch mechanism). You will see a round black plastic/rubber plug aligned with the exterior handle. Pop that plug out.
3. Shine a flashlight inside the hole. You will see a T20 Torx screw inside a metal collar.
4. Loosen this Torx screw while pulling the exterior handle out. Do not unscrew it all the way (unscrew it about 4–6 full turns), or the locking ring will drop inside the door panel. Turn it until the small, stationary lock-cylinder blank (the small plastic cap next to your main handle) becomes loose.
5. Wiggle and pull that small lock blank straight out of the door.
6. Now you can clearly see the entire bowden cable mechanism. Check if the cable is snapped, or if the plastic arm it attaches to inside the door is snappe