Drag-and-Drop Illustrator to Excel

I work in the area of garment manufacturing and I often create technical packs where I will draw an image on illustrator and drag it over to a large merged cell within the Excel sheet I am currently working on. However, all of a sudden this feature no longer works and my Mac makes that dreadful "Boop" sound when it denies you the ability to do something. When I then try Copy and paste, it will just paste gibberish. I even tried Paste special, however this only allows me to use the PDF setting and makes these tech packs humungous files. I just would like to know how to go back to the drag and drop method I was using earlier...