mail.mserv.top has an A (IPv4) record (155.138.161.117) 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 mail.mserv.top/155.138.161.117: Get http://mail.mserv.top/.well-known/acme-challenge/letsdebug-test: context deadline exceeded
Trace:
@0ms: Making a request to http://mail.mserv.top/.well-known/acme-challenge/letsdebug-test (using initial IP 155.138.161.117)
@0ms: Dialing 155.138.161.117
@10001ms: Experienced error: context deadline exceeded
A test authorization for mail.mserv.top to the Let's Encrypt staging service has revealed issues that may prevent any certificate for this domain being issued.
Fetching http://mail.mserv.top/.well-known/acme-challenge/UDJ4inIrS1iexfY9eJGFmTyoI8Fc8clNqO-EKAsSHBY: Timeout during connect (likely firewall problem)