Loss of featured offers

Why have I suddenly lost all of my featured offers? For some ASINs my price is even 20 euros lower, but still I am not winning buy box. Regarding account health, I have 0 negative feedback, 0 a-to-z claims, delivery is 100% on time, no late dispatches or pre-cancelled orders. So what are some other things that may have impacted this? It is quite frustrating to lose all of the featured offers for no apparent reason.