Question regarding Excel-based BOM

I am relatively new to Solid Works. Our company uses theExcel-based table to create our assembly bills of material. If Iedit the BOM by double-clicking, make changes, close the BOM, andsave the drawing, my changes are okay. If I close the drawing, openthe associated model to make a non-BOM related change, save themodel, then re-open the assembly drawing, all of my edits revertback to the original text, quantities, etc.

Can someone please explain how the Excel based BOM works, and whatI can do to eliminate this editing problem? It is getting veryfrustrating...

Thanks!
SolidworksBill Of Materials