uncensored content in pixiv fanbox

I am trying to be a nsfw artist on pixiv fanbox but I am having some irregularities and I am afraid of being banned, I know that you should not post uncensored pictures but I thought that only applied to public posts for all users, I uploaded an illustration of freminnet which falls under the 500 plan I have, but they sent me a message saying they had archived the post because it shows uncensored content on genitalia, I see many artists promoting their paid posts as uncensored versions of their public works so I don't understand. someone help me understand how to use fanbox or what am i doing wrong?