This was working fine as of 11/7/25. Now I am unable to send user verification emails from a Django site on a AWS lightsail sever. When a user attempts to register the following error occurs. I have also attempted to send a test email via the shell and I get a similar error:

end: 'ehlo ip-xx-xx-xx-xx.us-east-2.compute.internal\r\n'

reply: b'250-mx.zohomail.com Hello ip-xx-xx-xx-xx.us-east-2.compute.internal (ec2-13-58->

reply: b'250-STARTTLS\r\n'

reply: b'250 SIZE 32505856\r\n'

reply: retcode (250); Msg: b'mx.zohomail.com Hello ip-xx-xx-xx-xx.us-east-2.compute.inte>

send: 'STARTTLS\r\n'

reply: b'220 Ready to start TLS.\r\n'

reply: retcode (220); Msg: b'Ready to start TLS.'

send: 'ehlo ip-xx-xx-xx-xx.us-east-2.compute.internal\r\n'

reply: b'250-mx.zohomail.com Hello ip-xx-xx-xx-xx.us-east-2.compute.internal (ec2-13-58->

reply: b'250-AUTH LOGIN PLAIN\r\n'

reply: b'250 SIZE 32505856\r\n'

reply: retcode (250); Msg: b'mx.zohomail.com Hello ip-xx-xx-xx-xx.us-east-2.compute.inte>

send: 'AUTH PLAIN AGFkbWluQGNhZmVmbGVldC5jb20ASnFqS2tQRmQwNDdl\r\n'

send: 'quit\r\n'

SMTP error: Connection unexpectedly closed

Traceback (most recent call last):

  File "/home/ubuntu/sitecom/zoho_test.py", line 34, in <module>

    server.quit()

  File "/usr/lib/python3.12/smtplib.py", line 993, in quit

    res = self.docmd("quit")

          ^^^^^^^^^^^^^^^^^^

  File "/usr/lib/python3.12/smtplib.py", line 431, in docmd

    self.putcmd(cmd, args)

  File "/usr/lib/python3.12/smtplib.py", line 378, in putcmd