unifi.avsion.com.au has an A (IPv4) record (122.106.37.27) 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.
Get http://unifi.avsion.com.au/.well-known/acme-challenge/letsdebug-test: dial tcp 122.106.37.27:80: connect: no route to host
Trace:
@0ms: Making a request to http://unifi.avsion.com.au/.well-known/acme-challenge/letsdebug-test (using initial IP 122.106.37.27)
@0ms: Dialing 122.106.37.27
@7343ms: Experienced error: dial tcp 122.106.37.27:80: connect: no route to host
A test authorization for unifi.avsion.com.au to the Let's Encrypt staging service has revealed issues that may prevent any certificate for this domain being issued.
Fetching http://unifi.avsion.com.au/.well-known/acme-challenge/2CLnjGHQAHzRXT_7yEyr2ehGFXZi425buQWUQXfRWtI: Error getting validation data