Hi David Janson,
Thank you for posting in community. I know how frustrating it can be when your Slim Pen 2 stops inking especially after trying tip replacement and re-pairing. You're not alone other users have experienced similar issues. There are things that have helped others, First, try going into Device Manager, uninstalling "Intel(R) Precise Touch and Stylus" and removing any hidden or unattached HID-compliant devices, then scan for hardware changes. Second, make sure your pen is docked or charging during Windows Updates so firmware updates can apply properly. Third, reset the pen by holding the top button for 5–7 seconds until the LED flashes, then re-pair it via Bluetooth.
Let me know if you'd like help walking through any of these steps. We're here to help.
Best,
Carl