mrs.dsg.dk has an A (IPv4) record (109.236.189.11) 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://mrs.dsg.dk/.well-known/acme-challenge/letsdebug-test": dial tcp 109.236.189.11:80: connect: connection refused
Trace:
@0ms: Making a request to http://mrs.dsg.dk/.well-known/acme-challenge/letsdebug-test (using initial IP 109.236.189.11)
@0ms: Dialing 109.236.189.11
@16ms: Experienced error: dial tcp 109.236.189.11:80: connect: connection refused