When you attach a 3 or 4 dial code lock to the new style buildings once taken on nasdara it attaches fine. But when you remove it and try and reattach it. It will not let you re attach it. Using a new code lock the have been used on the door before will let you re attach.

Set code and attach to door. Detach lock and exit the base and try and reattach attach and it will not.