Calvin Klein crop top zip up

This is a good condition as far as rips in quality go because I bought it like five years ago and I hardly ever wore it, but when I did apparently I stained it somehow because after grabbing it out of my closet after like four years there was a brown stain on it, and I don’t know if you could wash it out or notI haven’t tried to wash it yet it has no rips but it does have one stain. I’m not sure if it can come out or not or where it’s from but it’s brown it’s definitely not poo though so don’t freak out the stain is on the pocket area, which you can clearly see, just in case you missed it, because it kind of does blend in with the grey colour of the Hoodie