You’re not going to get this exchanged after this much time has passed. Maybe if the scratch is underneath the glass, which I can’t clearly see on this crappy picture.
But I wouldn’t waste my time on something like this when the chance of succes is something like 0.1%.
Even when in a case your phone can get scratched, especially if you never have taken it out to clean or something… and when you have taken it out of it’s case there’s a chance you damaged it without knowing.
So don’t bother.