It sounds like you've already tried several troubleshooting steps for your Surface Pro 9 and the Surface Slim Pen 2. Here are a few additional suggestions you might consider:
- Check the Pen Battery: Ensure that both pens have a working battery. If the indicator light shows solid red or no light, replace the battery with a new AAA battery.
- Re-Pair the Pen: Try unpairing and then re-pairing the pens with your Surface Pro 9. To do this, go to Settings > Devices > Bluetooth & other devices, find your pen, and remove it. Then, follow the pairing process again by holding the top button until the light blinks.
- Update Pen Firmware: Make sure the firmware for your Surface Slim Pen 2 is up to date. You can check for updates in the Surface app or through the settings.
- Check for Windows Updates: Sometimes, Windows updates can resolve compatibility issues. Ensure your Surface Pro 9 is fully updated.
- Test in Different Applications: Try using the pen in different applications to see if the issue is specific to OneNote or if it occurs across all apps.
- Reset the Surface: As a last resort, consider resetting your Surface Pro 9 to factory settings. Ensure you back up your data before doing this.
If none of these steps work, you may need to contact Microsoft Support for further assistance or consider getting a replacement pen if they are still under warranty.
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