This error now happens in dnscrypt. I believe there were some certificate changes recently.
[CRITICAL] [quad9-doh-ip4-port443-filter-pri] Certificate hash [2a15f5d6acb6e7c0901ade4ebbc743b2ccd489032b46e1642f0693683001258a] not found
[CRITICAL] [quad9-doh-ip6-port443-filter-pri] Certificate hash [2a15f5d6acb6e7c0901ade4ebbc743b2ccd489032b46e1642f0693683001258a] not found
This error now happens in dnscrypt. I believe there were some certificate changes recently.