Hi Atlassian Community,
I am an Agent/Admin in JSM in the Cloud and struggling with an issue.
I have tried to add a secondary email account to the "Email requests" option under the JSM Projects field (as below).

Whilst performing some tests, I noticed the email handler fails to provide a auto-reply to an external email account. After inspecting the "view logs" of the email account ending with .....@....world.com above, I noticed JSM generates a Customerfield_10051 message (see below):

Here is a hypothetical case where this email handler fails:
a. support@companyworld.atlassian.net and
b. helpdesk@companyworld.com
Here is a hypothetical case where this email handler actually does work:
a. support@companyworld.atlassian.net and
b. support@company.com.au
Can someone explain why the different email combinations work in one instance and not the other?
I am not sure where to find this field, so I don't know how it got modified in the first place. So I was hoping that someone can point me to where in the JSM project can I edit the value 'customerfield_10051' field?
Regards,
Alex