Writing to the config too many times

So the plugin should test if the block under a player is blue/red wool, and if so it adds them to the config and if not it removes them, but it keeps adding a player continously and when i checked it i saw this:


Anyone see why it would keep adding it to the config?

Relevant code:

Code (Text):

public class GameStart implements Listener {
    Main pl;
    public GameStart(Main pl){
        this.pl = pl;
    }
    List<String> red = new ArrayList<String>();
    List<String> blue = new ArrayList<String>();
    @EventHandler
    public void onPlayerMove(PlayerMoveEvent event){
        TeamData td = new TeamData(pl);
        FileConfiguration teams = td.getData();
        Player p = event.getPlayer();
        blue.addAll(teams.getStringList("Teams.Blue"));
        red.addAll(teams.getStringList("Teams.Red"));
        if(p.getWorld().getName().equals("world_nether")){
            Block b = p.getLocation().getBlock().getRelative(BlockFace.DOWN);
            if(b.getState().getData() instanceof Wool){
                Wool wool = (Wool) b.getState().getData();
                DyeColor dc = wool.getColor();
                if(dc.toString() == "BLUE"){
                    if(!teams.contains("Teams.Blue." + p.getName())){
                        blue.add(p.getName());
                        if(teams.getStringList("Teams.Blue").contains(p.getName()))
                            teams.set("Teams.Blue", blue);
                        td.saveData();
                    }
                }else if(dc.toString() == "RED"){
                    if(!teams.contains("Teams.Red." + p.getName())){
                        red.add(p.getName());
                        if(teams.getStringList("Teams.Red").contains(p.getName()))
                            teams.set("Teams.Red", red);
                        td.saveData();
                    }
                }
           }
    }
}