How to say “Someone has filled the book return box again, and my books won't fit through the slot.” in Japanese
In Japanese
誰かがまた返却ボックスをいっぱいにしちゃって、私の本が投入口に入らない。
Dareka ga mata henkyaku bokkusu o ippai ni shichatte, watashi no hon ga tōnyūguchi ni hairanai.