What version did you update from? Most version updates (upgrades if you go from V8 to V9) will convert your Lightroom Classic catalog to a new version. Chance are, you are using a new catalog with no images imported yet. Search your hard drive(s) for "lrcat" files in windows explorer or Mac Finder. When you find the lrcat files, double click on the one that has the date from just before you updated Lightroom Classic. That will open it or LrC will ask to convert it. Go ahead with the conversion.