What's the Name of That Book??? discussion

The book I am looking for had a blue cover and a one word title I believe. It was a dystopian fiction. It featured a male protagonist who goes to do a favour for his teacher at his exclusive school at the top of a school caste system. He gives his jacket to his friend and his friend is subsequently killed because he was wearing the jacket. After his friend is killed, the main protagonist goes back to his exclusive school but seemingly no one remembers him and he isn’t in the system in his school anymore. Thinking he is an intruder, they take him to the bottom school in the school caste system which is very violent and the pupils are sort of animalistic. I think they get taught whilst in cages. Possibly some sort of fight club in that school. There is also a “beyond” area which is where people who refuse to go to the schools go I think or possibly people that also had their identity wiped.
Any help would be greatly appreciated. I think I read the book between 2012 and 2016 but I have no idea when it was released.

I remember reading something like that, but I don't remember the title. I asked chat GPT and it said it could be "The Testing" by Joelle Charbonneau

It is The Disappeared by C.J Harper. I just figured it out.

Glad you found your book, Charlotte.

The Disappeared (book 1) of the The Disappeared series by C.J. Harper