FYP country changed

Hi, Before the tiktok ban my fyp was mostly us and uj creators and my posts were shown to uk people mostly. Since then it often shows irrelevant coutry's posts and my posts are shown 90% to Hungarian people, altough my content is in English. Did they change something with the algoritm? Can I change it back somehow? And also is there anything I can do to show my post to people, who are interested in my content ( books)? I follow such people, but the app does not show anything to my followers and engagement rate is really low. Views are around 800. Thanks