Hi @David Tissen,
Per my research, there is some issue with SharePoint Online content search currently. This issue specifically impacts items which were newly created or updated recently.
As the picture shows, Microsoft will fix the issue in next update. The update should be in Friday, February 9, 2024 at 6:00 AM GMT+8. And we will continue to pay attention to this issue. Thanks for your understanding.
Here is a report similar with yours in admin center
https://admin.microsoft.com/adminportal/home?#/servicehealth/:/alerts/SP709902
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