Some Signs do not seem to work. I have buy and sell SPAWNERS signs, and other signs, some signs work some do not. I get no errors, permissions are 100% correctly setup, and some signs do work. When the player is opped, all signs work for them.

maybe its the region or its under spawn protection in server.properties make spawn-protection 0 then restart the server and try

Can you paste your permissions file please.

Closing due to inactivity. If this is still a problem, please open a new issue.