I was able to figure this out! So, you have to be sure to include the same item code to reference in the description line, and double check that you are linking the cost code and item list files located in <C:\Users\****\AppData\Roaming\SketchUp\SketchUp 2019\SketchUp\Plugins\Estimator\db> folder. You should keep the items database file and the code list that you use in this folder. It sounds redundant, but I just spend hours troubleshooting this simple thing. : ) I hope this helps anyone else who has this problem.