mrrobotcloud.duckdns.org has an A (IPv4) record (76.70.59.54) 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 mrrobotcloud.duckdns.org/76.70.59.54: Get "http://mrrobotcloud.duckdns.org/.well-known/acme-challenge/letsdebug-test": context deadline exceeded
Trace:
@0ms: Making a request to http://mrrobotcloud.duckdns.org/.well-known/acme-challenge/letsdebug-test (using initial IP 76.70.59.54)
@0ms: Dialing 76.70.59.54
@10002ms: Experienced error: context deadline exceeded
A test authorization for mrrobotcloud.duckdns.org to the Let's Encrypt staging service has revealed issues that may prevent any certificate for this domain being issued.
76.70.59.54: Fetching http://mrrobotcloud.duckdns.org/.well-known/acme-challenge/IR4wrqCKs3kiLt47UPTI_8zCHca02h8tEhiOD1ZHWaA: Timeout during connect (likely firewall problem)