I am left scratching my head on two listings that I have sold for years alongside other sellers. In these listings, I used to rotate the Buy Box alongside everyone else. In both cases, new sellers that came online a few months ago have absolutely dominated the Buy Boxes even though all offers are the same with regard to FBA, price and inventory level (These are MAP priced and only approved sellers). My account health is stellar, I had plenty of volume on these listings previously, and I have plenty of inventory, as well as full FBA offers with same day delivery. Nothing has changed, except for the fact I now only see less than 1% of the sales that I should be seeing. One of the sellers is Tiger Health, and I see them dominating other listings as well. Is this some new technique that I am unaware of or simply a glitch in the algorithm?

In yet another case, there is a seller that is in my same industry, that has listed multiple items that I am also able to obtain and sell, but Amazon indicates I am not eligible to be featured in the buy box. It appears they have set up the listing in a way that prevents anyone but them from having that placement, and I cannot figure it out. Even drastic price reductions do not seem to fix it. It spans multiple categories and multiple listings.