A test authorization for iseries.world to the Let's Encrypt staging service has revealed issues that may prevent any certificate for this domain being issued.
99.247.240.88: Fetching http://iseries.world/.well-known/acme-challenge/5A2LQEWgASX3JF3cVvwAcPjD-COd8ksy-F1mkzoMUu0: Error getting validation data