Vintage T-Shirt Forum & Community Authentication Appraisals

I have a 100% dirty Sonic Youth t-shirt, Gildan ultra cotton tag, long sleeve, brown color. I got this t-shirt at an auction from a famous vintage t-shirt seller in my city. But why is it that Grailed and eBay say this t-shirt is fake? Even though I saw other seller's listings, with the same tag, the same color, even Justin Reeds has it. Can anyone help me explain? Thank you

nothing's wrong by the look of it, and see no reason why would anyone faked it, i think it's good
also ebay authentication is kinda on and off, for grailed authentication, it's worse, they'be been known to authenticate the fakes and vice versa, so it's no surprise