Certificates are not getting renewed automatically

I thought certs generated on the fly by this plugin had automatic renewal as well, but I just found out a bunch of domain's we're supporting can't be accessed because the cert is expired. I need to renew them urgently. What can I do?

The issue names no source file, test, or entry point. Start by tracing the plugin’s on-the-fly certificate and Let’s Encrypt renewal flow in an OpenResty/nginx setup; done means supported domains no longer serve expired generated certificates and the renewal behavior can be verified.

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