NEED ADVICE* How to appeal false counterfeit claims.

A seller is claiming my products are counterfeit even though I have brand approval in my applications. I did some research and this person “Jesus Fuentes” made the claim and he does not actually own the rights to the brand, it seems he is just trying to win the buy box. What is the best way to appeal this claim? The product is a blank coffee mug with text printed on it. How can I counter this with Amazon so this guy has to show proof he is the actual rights owner?