Because sliding patio doors are used a lot it s common for their locks to occasionally jam or break.
Sliding door lock broken.
First remove the screws securing the door handle in place first with your phillips screwdriver and slide the outer latch lever out of place.
Remove the broken sliding glass door lock from the door by removing the screws that attach it to the door.
In this video i attempt to open a patio door that has got stuck locked.
While you might need to completely replace your lock it s possible you just need to replace the latch.
Take the old door lock to your local hardware store to use as a reference when purchasing a new door lock.