Not much you can do about it today in Feb2021. Microsoft and Autodesk are not interested in ever finding out why. Win10 breaks licenses after OS updates for many users. Your AutoCAD/LT2009 is not supported in Win10, which means Autodesk is not interested ever in helping you with any issue, it does not mean anything else you might read into 'supported'
But we know the following that we are sharing with you.
