How I fixed tenant access fobs that would not sync after move-in

I ran into this in a mixed-use property where retail tenants received access fobs through a cloud access control system. The issue was new tenant fobs worked at the lobby door but failed at the back-of-house corridor reader. At first I blamed bad fob cards, but it showed up whenever a tenant was added from a copied access group during a weekend move-in. This caused staff had to escort employees…