Mail failing at gmx.com domain

When I check dnsbl web site for bl and spam it’s shows “ok” for all categories with this message

Spam Database Lookup Results for 142.93.80.222

rDNS/PTR record for 142.93.80.222 is “box.danmarotta.com”.

Some mail servers will not accept mail from IP addresses with no rDNS/PTR record or a generic PTR record.