I am in middle school and youknow those slots some one stuck a cig in it and i got detension4 it wat do i do?

in my school for my locker and someone stuck a cigerett in it and a techer walked bye amd i got in detenison and i get the talk every day and i tell my parents i would never smoke be cause it can kill you but the didn't lisen what should i do i don't want to get in any more troble