Cannot retrieve mime content anymore of a mail message for a specific user

Question

Hi,

We have developed an application that uses Microsoft Graph API to access outlook mailboxes of users, and extract the mime content of the mail messages.
The application is running over 5 years now with no issues. But since recently (few weeks) the specific call is not working anymore.

The request uri is:

https://graph.microsoft.com/v1.0/users/9004bc34-7d6f-4632-9008-3e93ff54743a/messages/AAMkADA5ZTdiYjIzLWUyMjQtNGJmZC1hZGQ1LWY2Y2NhMjQ0MDI3MwBGAAAAAAA09XfcVBv3QIX-mTPdNbcUBwDgLMMV09ozQa8DVOCJWzJ5AAAAAAEMAADgLMMV09ozQa8DVOCJWzJ5AAdprgedAAA=/$value

Using Microsoft Graph explorer we can see the actual error:
However the SysAdmin of the company confirmed there were no changes to the server mailboxes.

{
    "error": {
        "code": "ErrorMailboxMoveInProgress",
        "message": "Mailbox move in progress. Try again later., Cross Server access is not allowed for mailbox 09e7bb23-e224-4bfd-add5-f6cca2440273"
    }	
}

However. Getting the mime content given the user id of the logged on user is working correctly.

Kind regards
Dennis