GTIN Exemption

Can’t add a product although I have a GTIN Exemption for the Category.
Everytime I end filling all the required filleds it takes me back to the " Product Identity" stating that I need a GTIN Exemption although it accepts it when I first fill it in. It just shows that message after I finish filling all the required fields
The Category I’m trying to add a product is PC & Video Games>Legacy Systems>Sega Systems>Sega Saturn> Other (Sega Saturn)

Does anyone knows why this might be happening?

Thank you