I am creating Assembly drawings using AutoCAD 2017. All of my assembly drawings are created using blocks that contain parts references. When I insert the blocks, the BOM gets updated with the correct part references and quantities. My problem is that I have to check to make sure the quantities of items I have in my drawings match the ones showing in the BOM. Sometimes, the quantities in the BOM display more than there are in the actual drawing. Even after I remove all the blocks, a quantity of 1 still shows in the BOM. That specific block is not found anywhere in the drawing. The only way to remove it is to purge it and re insert the block. This is very annoying specially if I have the drawing completed or there are more than one part displaying the wrong quantity. Has anyone seen this before and is there a way to remove that "ghost" entry without having to remove all the blocks and re insert them. Thank you. 

Deleting the blocks of one type then purging the block definition removes it from the drawing and also from the BOM. This is the method I have been using since I can't find a solution to removing the extra quantity in the BOM, which is my problem, since after deleting and purging I have to re insert all the blocks again.