unifi.penntech-it.com has an A (IPv4) record (51.140.36.218) 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 unifi.penntech-it.com/51.140.36.218: Get "http://unifi.penntech-it.com/.well-known/acme-challenge/letsdebug-test": dial tcp 51.140.36.218:80: i/o timeout
Trace:
@0ms: Making a request to http://unifi.penntech-it.com/.well-known/acme-challenge/letsdebug-test (using initial IP 51.140.36.218)
@0ms: Dialing 51.140.36.218
@10001ms: Experienced error: dial tcp 51.140.36.218:80: i/o timeout
A test authorization for unifi.penntech-it.com to the Let's Encrypt staging service has revealed issues that may prevent any certificate for this domain being issued.
51.140.36.218: Fetching http://unifi.penntech-it.com/.well-known/acme-challenge/xxJsKyCcKFdw2kxCoBCaZp_VWvyN_uhpE78LTsdAqEY: Timeout during connect (likely firewall problem)