Hello @jbooze ,
I am afraid you can't clear Data Protection Alerts. Just perform a Consistency check in order to clear, and check if that works.
You can consolidate alerts in the console. You can display a single alert for repeated alerts, or display a single alert for multiple alerts that have the same root cause. If you're using a ticketing system, you can generate a single ticket only for repeated alerts.
For further details, check the below link
https://learn.microsoft.com/en-us/system-center/dpm/monitor-dpm?view=sc-dpm-2019
Hope this answers all your queries, if not please do repost back.
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