This is the mechanism inside the door that is operated by the handle. It is most likely to be the problem when the lock fails. It can be attached to the old locking strip and is more cost effective than replacing the whole multipoint lock. It is non-handed and available in 35mm and 45mm backset sizes.

Brand Name	TRULY PVC LIMITED
Colour	N/A
Material	N/A
Manufacturer Model No	5060070044989
Wear Type	N/A
Type	Door Lock
Certifications Met	N/A
Country of Origin	N/A
Protects From	N/A
Waterproof	N/A
Number of Pockets	N/A
Backset size	45mm
Guarantee	1 year