Try these steps in order:
- Put the pen back into pairing mode.
- In Windows 11, most pens enter Bluetooth pairing mode by pressing and holding the top button for about 5–7 seconds until the LED flashes continuously.
- Re-pair it in Windows.
- Go to Start > Settings > Bluetooth & devices.
- Make sure Bluetooth is turned on.
- Select Add device > Bluetooth.
- Select the pen name, such as Surface Pen, then finish with Done.
- If the pen does not appear in the device list, check the pen battery.
- If the top-button LED shows amber or red, the battery is low and needs to be charged or replaced, depending on the pen model.
- Check for updates.
- In the Surface app, expand Help & support and check update status.
- If updates are available, select Check for updates to open Windows Update and install them.
- If this is a Surface Pen and the problem started after an update or sleep-related pairing issue, install the available Windows update.
- Microsoft released an update for a known issue where a paired Surface Pen could show "Not Connected" instead of "Paired".
- After installing that update, the status changes to "Paired".
- A restart may be required after the update.
If the pen still will not connect, the next useful check is whether the issue is only with the pen or with Bluetooth in general by trying another Bluetooth device.