Brand Registry violation reporting

Hello,

I have a Brand Registry account, and my trademarks are registered and approved. Our products are sold by multiple distributors in Europe. However, many sellers on Amazon are not our direct customers (for example, only five out of 30 sellers are our customers). How can the Brands Registry help me tackle this problem? I don’t have any clear reason to report them; at least none of the listed in the Brands Registry apply to me. My consultants say that I should report unauthorized sellers on a copyright or parallel import basis; however, that would not be true. What can I do?