5HTP supplements - Amazon removed mine but allows others to sell them - why?

6 months ago Amazon removed my listing page as 5HTP , an ingredient in my product, is a novel food. 6 months later I can still find hundreds of supplement products with 5HPT in them, in all doses and combinations. Why are Amazon being so inconsistent? Any ideas how i get my listing back? Amazon will not discuss other people's business, only my own, which violates their rules. Any advice?