The Microsoft 365 audit log holds all kinds of useful data, including events logged for SharePoint Online and OneDrive for Business file deletions. It’s easy to use PowerShell to search the audit log to find and interpret the events and create a report. Large tenants might need to export the audit data on a regular basis to an external repository to allow for long-term retention and analysis. We explain the principles of the process in this article.
https://office365itpros.com/2021/12/16/search-microsoft-365-audit-log-document-deletion-events/
