dev.lubyc.com has an A (IPv4) record (34.66.232.202) but a request to this address over port 80 did not succeed. Your web server must have at least one working IPv4 or IPv6 address.
A timeout was experienced while communicating with dev.lubyc.com/34.66.232.202: Get http://dev.lubyc.com/.well-known/acme-challenge/letsdebug-test: dial tcp 34.66.232.202:80: i/o timeout
Trace:
@0ms: Making a request to http://dev.lubyc.com/.well-known/acme-challenge/letsdebug-test (using initial IP 34.66.232.202)
@0ms: Dialing 34.66.232.202
@10000ms: Experienced error: dial tcp 34.66.232.202:80: i/o timeout