Can't find our Asin even by searching our brand

We recently noticed a wierd issue happening to 2 of our asins.

They are active, we can find our product through searching keyword related to the asin. BUT we cannot find our product by searching our brand. We have been selling these 2 asins for our 2 years and they were always there when we search products by our brand. But they dissapeared when we tried to search our products by our brand a few days ago and although we can still find the product by using related search terms, all the Amazon's Choice tag related with these 2 asins are gone.

We checked with seller support, these 2 asins are neither labeled as adult product nor hazardous products.

Anyone experienced or experiencing the same issue ?

Many thanks