Problem / tpyes command: an internal error occurred while attempting to perform this command

I wanted to create a system so that each Team is teleported to its Spawn with the / tpyes command but it doesn't work, when I use the in-game command it sends me back "an internal error occurred while attempting to perform this command " Can you help me ? (Sorry for bad English)

My code:

public class CommandTest implements CommandExecutor {
private Main main;

@Override
public boolean onCommand(CommandSender sender, Command cmd, String msg, String[] arg) {



if(sender instanceof Player) {
Player player = (Player)sender;

Location BlueSpawn = new Location(Bukkit.getWorld("world"), 84.687, 58.0, -88.526, 90.0f, -1.6f);
Location YellowSpawn = new Location(Bukkit.getWorld("world"), 72.499, 58.0, -72.300, -179.6f, -1.6f);
Location RedSpawn = new Location(Bukkit.getWorld("world"), 60.300, 58.0, -88.471, 90.3f, -1.6f);
Location GreenSpawn = new Location(Bukkit.getWorld("world"), 72.483, 58.0, -104.700, -0.0f, -1.6f);

if(cmd.getName().equalsIgnoreCase("tpyes")) {

if(main.getBlueteam().contains(player)) {

((Entity) main.getBlueteam()).teleport(BlueSpawn);
((CommandSender) main.getBlueteam()).sendMessage("§5Vous avez été téléporté !");

} else if(main.getYellowteam().contains(player)) {

((Entity) main.getYellowteam()).teleport(YellowSpawn);
((CommandSender) main.getYellowteam()).sendMessage("§5Vous avez été téléporté !");

} else if(main.getRedteam().contains(player)) {

((Entity) main.getRedteam()).teleport(RedSpawn);
((CommandSender) main.getRedteam()).sendMessage("§5Vous avez été téléporté !");

} else if(main.getGreenteam().contains(player)) {

((Entity) main.getGreenteam()).teleport(GreenSpawn);
((CommandSender) main.getGreenteam()).sendMessage("§5Vous avez été téléporté !");

}
return true;
}

 

Show the error.

 

Code:

if(main.getBlueteam().contains(player)) {

((Entity) main.getBlueteam()).teleport(BlueSpawn);

You are casting a list to an Entity, you cannot do that..