I keep dreaming of keys that don't fit any lock

I'm doing my rounds, same route I walked for thirty years, but every key on the ring slides into a lock and comes back out useless. The block is quiet the way it used to be at 2 a.m., and I'm trying to tell myself that silence is order, but in the dream I know it isn't — it's just me walking the same hallway, holding keys that were never mine.