Can't change "-2" on Product Attribute slug

I have about 90 products that I need to make searchable by product name in a pull down menu… So, I added all product names to the product attributes section, however of the 15 product names there are 3 of them that use the slug /product-2… I have nothing in the trash, but even when there is something in the trash it seems to be more related to product pages rather than attributes…

So how do I get rid of the -2 at the end of the slug? When I try to do “Edit” it just automatically puts it back in there for me. When I do a “Quick Edit” it tells me there’s another product using that slug… But where? And, what would that matter if I’m just trying to make an attribute?

Note: I had this issue once before related to the product page URL’s. When I went to add a product sometimes it would say -2 in the URL. I was able to resolve that by deleting the trash and refreshing several times. However, that does not seem to be the answer to my current issue.