Can't find item number

Hello, I have a WordPress site with a store where I sell my shirts and ties. When I get orders there is an item number associated with the product, but I can’t seem to find anywhere on the site that includes this number. Where do I find this?

Longwinded extra information: Here’s why it matters: I have some men’s and women’s shirts that have the same design and color and that have the very same main page title. The URL looks like this: https://www.scatterbraintees.com/products-page/men/abraham-lincoln-shirt/ You can see it’s in the men’s section by the link, but when I get an email about the sale there is nothing to distinguish whether it’s a men’s or women’s shirt other than this mysterious item number. I did the obvious and changed some of the titles to include either “men’s” or “women’s”, but it didn’t affect the emails I get because I’d have to change the permalink for that to make a difference. I’d rather not change the permalinks in case I lose some traffic that way.

Thanks for your help!