Restricted selling on Book category

I have been selling books since 2020. I never had any account issues, also my seller feedback is %100 positive. I never sold any fake books. But yesterday I magically got restricted adding books to Amazon. It still allows me to get sales from my existing lists. I am also able to list DVDs, etc. Did anyone experienced similar issue? Also is there a way to remove the restriction? (I called Seller support, they kept saying me that they are not accepting any more applications at the moment)