Hi @Kobus van Tonder ,
You can make the following attempts to see if they will solve the problem:
1.Use the Microsoft 365 Protection Center or the audit log report to check whether the item was moved or deleted. For more detail information,please refer to this article: https://support.microsoft.com/en-us/office/how-to-recover-missing-deleted-or-corrupted-items-in-sharepoint-and-onedrive-for-work-or-school-3d748edf-c072-46c9-81a4-4989056ebc87
2.Check whether the item is in the second-stage recycle bin for the affected site collection Manage the Recycle Bin of a SharePoint Online site collection
3.If the above steps don’t resolve the issue, you can try restoring your OneDrive or a shared library
If steps 1–3 don't resolve the issue, contact support. When you open a request, provide as much additional information as possible to describe your issue. For more information, see Contact Microsoft 365 support.(Microsoft 365 admin center ->> Support ->> Help & support)
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