553 5.3.0 alph749 DNSBL:RBL 521 64.119.211.111

Already sent 3 request to abuse_rbl@abuse-att.net with no response or fix.
Our emails are still blocked by ATT servers when the ptr issue append only for a few hours during an internet provider swap. It is fixed for almost 3 weeks now.
Please unblock 64.211.119.111 ASAP or let me know why you are blocking us.
 553 5.3.0 alph749 DNSBL:RBL 521< 64.119.211.111 >_is_blocked

We can't communicate with any of our correspondent using your services

contact me if you need more info