My Lock does not fit correctly on my door? Check the door thickness. If your door is less than 45mm you will not need to use the spindle extension and hub. Check the alignment of the latch and the 54mm hole. The latch must be centred of the hole and also ensure you have used the latch supplied with the product. If the lock is not installed correctly, you may damage the lock. If you are installing the lock over an existing door preparation, check that all drill holes are straight and as per the Unity installation template provided. IMPORTANT: The spindles must be engaged into the latch like below. If this is not correctly aligned you could damage your lock. If the lock is not installed correctly, you may damage the lock. If required, a 70mm backset latch can be purchased separately; Part number: Y530-222SC.