Hello DanielCoulson1,
Thanks for posting your concern here.
Please try to check if your pen is connected to another host device. The Bluetooth connection from the other device and your Surface Go 2 might be interfering the button to respond as intended. Otherwise, test your pen to another Surface device and see if it does the same issue. In the meantime, please run Surface Diagnostic Toolkit and check for Windows Update.****Restart the Surface after installing updates. Validate if the button functionality in Windows settings are set correctly. Go to Settings > Devices > validate that pen is paired: look for Surface pen, if so then proceed to > Pen & Windows Ink and validate all setting are what you expect.
Please let me know how the issue progresses. Don't hesitate to respond to this thread if there’s anything else that needs to be addressed.
Best regards,
StevenK