Smatermail server SmarterMail Enterprise 100.0.7719.31036 ( SmarterMail Diagnostics all pass)

Smartermail server has users that cannot receive mail from the dotloop mail servers. Their messages disconnect in the manner below. Some messages do get through but most do not.  All other incoming mail seems to be fine. We are just aware of this one domain. I cannot reach the sender server admins to discuss.

I am trying to confirm that there is nothing on the Smartermail server causing these to fail.

I have whitelisted the sending domain on the domain level.

I am not sure why it is adding "bounces" to the front of address either but on the message that delievered from dotloop, the message arrive with "bounces" appended.

Secondly, I'm not sure if there is a way to track if there are other incoming messages that are failing in the same way.

Smartermail server:mail.countryfarm.com (not real hostname, real hostname is set up properly, RDNS is OK)

from smtp log, one message all others are similar.  the one that I found that got through simply didn't disconnect.

[2021.04.26] 15:53:05.456 [192.254.122.57][44489167] rsp: 220 mail.countryfarm.com
[2021.04.26] 15:53:05.456 [192.254.122.57][44489167] connected at 4/26/2021 3:53:05 PM
[2021.04.26] 15:53:05.456 [192.254.122.57][44489167] Country code: US
[2021.04.26] 15:53:05.503 [192.254.122.57][44489167] cmd: EHLO o1.email.dotloop.com
[2021.04.26] 15:53:05.503 [192.254.122.57][44489167] rsp: 250-mail.countryfarm.com Hello [192.254.122.57]250-SIZE 31457280250-AUTH LOGIN CRAM-MD5250-8BITMIME250-DSN250 OK
[2021.04.26] 15:53:05.549 [192.254.122.57][44489167] cmd: MAIL FROM:<bounces+814510-32c2-bob=countryfarm.com@email.dotloop.com>
[2021.04.26] 15:53:05.549 [192.254.122.57][44489167] senderEmail(1): bounces+814510-32c2-bob=countryfarm.com@email.dotloop.com parsed using: <bounces+814510-32c2-bob =countryfarm.com @email.dotloop.com>
[2021.04.26] 15:54:05.551 [192.254.122.57][44489167] disconnected at 4/26/2021 3:54:05 PM
[2021.04.26] 15:56:07.638 [192.254.122.57][44489167] rsp: 250 OK <bounces+814510-32c2-bob=countryfarm.com@email.dotloop.com> Sender ok
[2021.04.26] 15:56:07.638 [192.254.122.57][44489167] Sender accepted. Weight: -2. Block threshold: 30.

Thanks