oleum.net has an A (IPv4) record (78.143.193.253) 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://oleum.net/.well-known/acme-challenge/letsdebug-test": dial tcp 78.143.193.253:80: connect: connection refused
Trace:
@0ms: Making a request to http://oleum.net/.well-known/acme-challenge/letsdebug-test (using initial IP 78.143.193.253)
@0ms: Dialing 78.143.193.253
@74ms: Experienced error: dial tcp 78.143.193.253:80: connect: connection refused
A test authorization for oleum.net to the Let's Encrypt staging service has revealed issues that may prevent any certificate for this domain being issued.
Fetching http://oleum.net/.well-known/acme-challenge/jDwQX7p68HXH1H41BbgnPG9lu2olA0vwlFRT2BJGBcI: Connection refused