Have a similar lock. The doorknob on the inside fell off! Cannot put it back- do not see how it can be re-attached. The lever knob on the inside, to lock the dead bolt, also fell off, but that can be re-attached. This is the front door, which isn't used all that much. Now it is impossible to get out of the front door from the inside. Need to remedy this asap, so that in an emergency we can get out! Seems a terribly premature failure. The set we have was installed professionally, and is several years old. Not impressed at all.