i can't buy any books in my region and i don't even see them

On iPhone I can see the entire free library, but I’m unable to find any books available for purchase. The “Featured” section is also missing. When I follow a link to any book from the browser, I receive an error: “The item you have requested is not currently in the store for your country or region” My region is set to Ukraine, and I cannot access any Ukrainian books as well.

I’m able to make purchases in iTunes and subscribe to other Apple services without any issues. Additionally, I cannot open either “Manage Hidden Purchases” or “Account Settings” from the app. It prompts me for verification, but this ultimately fails with a verification error.

In the purchase settings, I’m unable to change the iCloud region, as

it requires a valid bank account and physical mailing address from

another country (if I’m not mistaken). I can only change the region

under Language and Region, but this has no effect.