Are you using the built-in Playbook or creating your own? https://github.com/Azure/Azure-Sentinel/blob/21aee31590f3440dc028be82ce638474b636bafc/Solutions/AtlassianJiraAudit/Playbooks/Sync-AssignedUser/readme.md If the built-in one works then you could use that 'as is' or amend, or just look at how they do this.
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