Unable to assign an issue automatically when created via email

[Mohajit Acharya]

My JIRA Cloud instance is having a problem where the following error message appears in Mail Handler, preventing issues getting assigned and setting watchers as per the names in CC of the incoming mail.

Please note, the issue is getting created successfully but it is in unassigned state. Although, we are mentioning assignee's email id in cc of the incoming mail.

Summary:
1 message read from the server.
Found 1 unprocessed message(s) in the pop3s folder.
Potential mail loop detected. Message will be removed.
Deleting Message 'Re: Atlassian test'