The original message was received at Tue, 24 Oct 2023 07:40:38 -0400 from a8-38.smtp-out.amazonses.com [54.240.8.38] ----- The following addresses had permanent fatal errors ----- <elena.kulchina@duke.edu> (reason: 550 5.1.1 <elena.kulchina@duke.edu>: Recipient address rejected: User unknown in virtual alias table) ----- Transcript of session follows ----- ... while talking to [152.3.70.26]:

...

...

DATA <<< 550 5.1.1 <elena.kulchina@duke.edu>: Recipient address rejected: User unknown in virtual alias table 550 5.1.1 <elena.kulchina@duke.edu>... User unknown <<< 554 5.5.1 Error: no valid recipients