Patio Sliding Door Lock issue ?

[bigdog]

Need suggestions regarding patio sliding glass door lock. When door is locked I have no way to open the door from the outside, as I don’t have a key.
There are no markings on door or lock.

Property is new to me and prior owner does not have a key.
Suggestions on how to find door model, brand, so I can get a key made without hiring a lock-smith.

Thanks !