@Shim Kwan Apologies for the delay in answering this post.
I wanted to test this behavior in my lab ( DLP Policy Notification keeps resetting ).
Tested this behavior in my lab, I don't see my DLP policies getting reset to default settings. Also would like to know how frequently you can repro this issue ?
However you can find the information in audit logs about the changes made to DLP Compliance Policy and DLP Compliance Rule
Connect to Security & Compliance PowerShell, execute the following command ( change the time stamp convert to utc according to your environment ).
Search-AdminAuditLog -Cmdlets Set-DlpComplianceRule -StartDate "2022-06-13 08:25:00z" -EndDate "2022-06-13 08:28:00z"
Look for caller information object id as shown in the screenshot above, is the one who made changes to the DLP Compliance Rule.
Further you can run this command Search-AdminAuditLog -Cmdlets Set-DlpComplianceRule -StartDate "2022-06-13 08:25:00z" -EndDate "2022-06-13 08:28:00z" | select -ExpandProperty modifiedproperties | FL to get new value and old value information of the modified properties attribute.
Let me know if you have any further questions or if you need further help we can connect offline to discuss further.
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