A cloud-based task management app from Microsoft that helps users organize and manage daily tasks across devices.
Hi Clara Kevek
Based on my research and testing, I recommend first checking the Deleted Items section to see whether the missing tasks are available there and can be restored.
Reference: Create tasks with To Do in Outlook | Microsoft Support
Additionally, you may want to sign out of the Microsoft To Do desktop app and then sign back in to refresh the account synchronization.
It would also be helpful to test Microsoft To Do on the web using an InPrivate or Incognito browser window.
I hope this information provides some additional insight.
If you have any updates or notice any changes after trying these steps, please feel free to share them.
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