If OneNote is not syncing maybe between devices, Teams, OneDrive, iPad, etc, then here are some practical working solutions to fix the issue.

OneNote sync failure error code: 0xE00009C8 typically occurs due to difficulties in syncing notebooks, preventing the data from being updated on all devices.

Microsoft has enhanced OneNote across the board, and rolled out updated iPhone, iPad, and Android apps to make it a more powerful tool for business users.