Hi mookie a,
Thank you for reaching Microsoft Community. I understand that you're having trouble calibrating your pen on your Surface Pro 9.
May I know which Surface Pen are you using with the Surface Pro 9? See this page for reference: Identify your Surface Pen and features - Microsoft Support
Also, which Surface Pro 9 configuration do you have? Intel or 5G?
Firstly, please note that Surface devices come from the factory already calibrated and optimized for pen and touch input to ensure the beast possible operation. Recalibrating the Surface manually or its default calibration changed for any reason, this might cause device issues. Please try using the Surface app instead and see if it helps. Open the Surface app on the device and select the Pen icon on the left. You will have the option to adjust pen pressure sensitivity.
Also, please check for the Surface drivers' health through the Surface app and run the Surface Diagnostic Toolkit on the device to run a system check and repair. Make sure also that all updates are installed including Optional updates. See: Fix common Surface problems using the Surface app and Surface Diagnostic Toolkit - Microsoft Support
Let me know how it goes and we may recommend other troubleshooting steps once we have received your responses to the questions above or if we need to refer you to the support that suits your problem, we will be sure to let you know in advance so that you save time.
Kind regards,
Marrion