Sometimes I get false alerts that resources are missing, even though they are clearly there if I inspect the inventory.
I'm not sure what triggers it, though, I just noticed it sporadically. The issue persists after reload. If I clear the output, then they start working normally, but the missing resource icon / status remains.
It's quite annoying, as it's hard to determine with a glance which buildings really need attention.
Save game:
https://drive.google.com/drive/folders/1OETWNMnPRPBpuhu23oKGnz_Lw7uJEVK-