Mystery (?) where teens play a game on a college campus (they don't go to the college though)

[Marie]

I don't remember much of the book, even though I have read it in 2018/19. It is about a group of high schoolers who play a game on their local college campus, I think they sometimes meet at some pizza place, but that might have been another book... I'm fairly certain it's some kind of mystery or crime book, but I really don't remember what happens, someone might have gone missing or being threatened or something. Please help!