Release the button quickly try sliding your finger off the button so the pressure is maintained up until the precise moment of release with no backing off.
Thumb press door handle sticking.
To test this firstly open the door and check that there are no obvious obstructions on the tubular latch plate such as loose screws or signs of internal parts of the latch or lock poking through.
Push and hold the button in.
The most common cause of sticking door handles is some kind of malfunction within the tubular latch itself.
Turn the handle of the doorknob to expose the bolt.
The issue a door latch stuck due to a jamming latch will have no real variation between how the latch moves when it is pressed in or when the handle is turned both when the door is open and when it is shut.
Once you let go of the knob grab the end of the latch bolt with your fingers and pull.
Remove the cap on the graphite powder.
Turn the knob to open the door and release the knob slowly.
Open the door and squirt graphite powder into the key lock.
If the latch bolt moves it is sticking in the door knob and requires some disassembly to fix.
Squirt the bolt with graphite powder.
This is because the issue is not with the door and not even with the control the knob has over the stuck latch.