As mentioned in https://www.phpbb.com/community/viewtopic.php?p=16054072#p16054072

RIPE is the assignment registry for IP addresses in that region. We start the whois lookup process with ARIN who only has responsibility over North America. In this case, the lookup indicates that this IP belongs to RIPE and provides information on how to look it up at RIPE. Most services provide a referral address indicating where their whois service is and then we follow that and look it up again on the new service. However, we look for a referral service prefixed with whois://. RIPE's entry no longer contains that prefix. They must have recently changed their entry at ARIN since this is no longer working.