Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Dear Viktoría Ósk Daðadóttir,
Good day!!
Apologies for the inconvenience caused and please don’t worry, let’s work together on your concern and move towards a resolution path.
I understand your concern and to my knowledge, I would like to let you know that only the owners of the Plan in the Microsoft Planner will be able to delete the Plan but the created Plan will be associated with the Microsoft 365 groups, and deleting the group will also delete the Plan associated with it.
However, not only the Microsoft 365 group can be deleted the admins in your Office 365 organization. So, please check with the Microsoft 365 admins of your Office 365 organization to see whether there is any deleted Group associated with the name of the Plan from the Microsoft 365 admin center. Reference: Restore a deleted Microsoft 365 group - Microsoft 365 admin | Microsoft Learn
Moreover, if the associated Group is still present in the Active Groups but Plan is deleted, then it seems the plan is deleted from the Plan Settings of the Plan in the Microsoft Planner, where only the Plan Owner has ability to delete it.
To find out the name of the user who deleted the Plan in the Planner, please connect with the Compliance Admin of your Office 365 organization for running the audit log with the Planner activities: Audit log activities | Microsoft Learn
Appreciate your patience and understanding. Have a great day!!
Best Regards,
Sophia