How the fluff do I clean this up

(idk what flair to use I'm sorry-)

I've had this 3ds since 2017 but I only now noticed this weird… thing? on my top screen while cleaning the screens. I had this 3ds when I was really young and because of that it has some small scratches (they're hard to tell from far) but I'm not sure if this is one or not

I hope it's not cause looking at it is making me insane 😭😭