From the error message "Archived entity can't be modified," I can see the issue is that Power Automate is trying to create a task in an archived Planner plan, bucket, or group. Even with a valid license, archived entities cannot be modified.
Here's what I'd suggest checking:
Check if your Planner plan is archived — Go to Planner, open the plan, and verify in the settings whether it's archived. If it is, you'll need to unarchive it first.
Verify your group/project status — Make sure the Microsoft 365 Group linked to the plan is active and not deleted or archived.
Confirm your permissions — Even with a license, ensure you have Editor or Owner access to the plan.
Refresh your connection — In Power Automate, try updating or recreating your Planner connection to ensure it has the latest permissions.
The error specifically indicates that something in the chain (plan, group, or task) is archived. Once you unarchive the relevant entity, your flow should work fine.
Try these steps and let me know if it resolves the issue! 👍
Vishnu WR
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