new CsTeams:g_p_team[33] //stores current team of every connected player
public player_change_team(id, CsTeams:new_team){
if (new_team == g_p_team[id])
return
client_print (id,print_chat,"You are not allowed to change teams!") //tell them they are not allowed to switch
user_kill (id) //slay them for switching
}