mrrobotcloud.duckdns.org has an A (IPv4) record (76.70.58.135) 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/76.70.58.135: Get "http://mrrobotcloud.duckdns.org/.well-known/acme-challenge/letsdebug-test": dial tcp 76.70.58.135:80: i/o timeout
Trace:
@0ms: Making a request to http://mrrobotcloud.duckdns.org/.well-known/acme-challenge/letsdebug-test (using initial IP 76.70.58.135)
@0ms: Dialing 76.70.58.135
@10001ms: Experienced error: dial tcp 76.70.58.135:80: i/o timeout
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.
Fetching http://mrrobotcloud.duckdns.org/.well-known/acme-challenge/EvMXobvNx1f5E4BOP8iaRh6jcD8hFTrss8LBWE1a5TQ: Timeout during connect (likely firewall problem)