Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Dear metoisa,
Good day! Thank you for posting to Microsoft Community. We are happy to help you.
Based on your description, You are getting an error “You do not have the required permissions to access this item, if the account used with graph does not belong to the planner group” when using MS graph for Planner.
After further research, it seems that there is currently no way to use MS graph to get all plans for a group without adding the account to all planner groups; this is a service limitation, and I notice that a feature request has been submitted to address it, see Application Permissions for Planner APIs - Microsoft Tech Community. Upvoting it will make it more visible to the service team, which will make it more likely that it will be implemented.
Thanks for your cooperation.
Sincerely,
De Paul | Microsoft Community Moderator
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