1. Check what the door is actually doing
Useful clues include whether the handle lifts normally, whether the key turns, whether the door locks when open, whether it catches the frame, and whether the problem has gradually become worse. These symptoms help separate an alignment problem from a failed locking component.
2. Alignment can mimic a lock failure
If a door has dropped on its hinges or moved out of alignment, the locking points may no longer enter the keeps cleanly. That puts extra load through the handle and gearbox. Replacing the lock without correcting the alignment can leave the new parts under the same strain.
3. Gearboxes and multipoint mechanisms can fail
Where the handle moves but does not operate the locking points correctly, the central gearbox or another part of the mechanism may be worn or broken. Correct identification normally requires manufacturer markings and measurements such as PZ centres and backset.
4. Security faults should not be ignored
If the door cannot be secured, treat it as a security issue and tell the repair company when you enquire. Avoid repeatedly forcing a stiff handle because that can increase load on already worn components.
What True Vision records
For locks and mechanisms we can record the door location, handing, opening direction, manufacturer markings, cylinder and mechanism dimensions, visible defects and supporting photographs. That information stays linked to the exact door for quoting and future maintenance.
Need someone to inspect the fault?
True Vision can turn the symptom into a measured repair scope and quote.