I have a batch of emails in which the Activity party table has been corrupted -- a non-existent Contact has been added to the To: line. I wrote a Power Automate flow that identifies the rows with the 'ghost user' in the Activity Party table, but I can't delete them. Response to the Delete is 'Bad Reequest' error even though I'm sure I'm passing the right GUID to the right tabIe.
I understand that Activity Party is a special table and even as system admin I apparently can't do a Delete. Any ideas how else to tackle this?