The user is seeing their email uploads being rejected or not received when they are forwarding them to the AutoEntry folder's email address.
Users uploading documents via email.
Microsoft has made some changes to the Outlook auto-forwarding system, wherein their own customer blocking has been implemented, preventing certain emails from being received once forwarded. More information about these changes can be found here.
Here are the steps to rectify this issue:
As an admin go to: https://protection.office.com/antispam
Open Outbound Spam filter policy and click Edit policy
2. Set "Automatic forwarding" on.
Additional reasons why your files might be rejected can be found here.