Outgoing Emails Not Visible Under Conversation Tab for Custom Role

I’ve created a custom role named "ABC" and assigned it to a user. When I log in using that user’s credentials and register a case, I’m unable to view any outgoing emails (sent automatically by the system to the contact) under the Conversation tab in the Case record.

This issue seems to be specific to the custom role, as the emails are not visible even though they should be generated during case registration.

This is urgent, and we would really appreciate it if someone could help us troubleshoot the root cause—whether it’s due to object permissions, column-level access, or any visibility rules.

Thank you in advance for your support.