I am using Odoo 17 Enterprise and having an issue with incoming emails.

If I send a message to a contact from the "Contact" itself, their responses to catchall email successfully received and recorded - including any attachments (if available).

So I guess there is no problem with the incoming/outgoing servers and catchall email settings.

But - when I send an email via "Send a message" button or Send a quotation / Purchase Order buttons etc. inside Sales Orders / Purchase Orders / Transfers (Operations), contact receives all emails and attachments without any issues, but their responses are not recorded / basically ignored. 

And if they send a response including an attachment - this time they get an auto response mentioning  This email cannot be processed. This address is used to collect replies and should not be used to directly (but we still do not get any notifications/emails in Odoo)

In a summary - we can send emails in every module, but can't get any email replies except to the "contact" module.

Any help would be greatly appreciated as I have searched all over the internet and could not find a solution.