new mail-account automatically forwards external mails to internal address

Hi,

last week I created a new mail-account to our outlook-users and added a mail-license.

Only internal mails was received in the new inbox and after troubleshooting and using mail-trace I discovered that the mails was forwarded to another internal inbox. This is not something that is configured anywhere in the mentioned settings when trying to troubleshoot forwarding-issues.

How do I turn this off, so that my new employee can receive external e-mails. We don't have any policies or rules set up, that should trigger this behavior.

Regards

Lars