The catalina.yyy-mm-dd.log shows the following error:
com.microsoft.graph.logger.DefaultLogger logError
SEVERE: DefaultHttpProvider[send] - 204 "message": "DeltaLink older than 30 days is not supported."
Each time an Office 365 Discovery is run, eDiscovery is updated with a new Graph DeltaLink token by Azure AD. This token is used when performing the next Office 365 Discovery to scan for incremental changes in Azure AD since the last discovery. This token is only valid for 30 days.
This issue is currently under investigation by Veritas Technologies LLC. Pending the outcome of the investigation, this issue may be resolved by way of a patch or hotfix in current or future revisions of the software. However, this particular issue is not currently scheduled for any release. If you feel this issue has a direct business impact for you and your continued use of the product, please contact your Veritas Sales representative or the Veritas Sales group to discuss these concerns.
Note: Customers experiencing this issue are encouraged to contact Veritas Technical Support as a work-around is available. Please reference this article when opening a support case.