BurnPlugin help

Hey! So I'm trying to make a plugin that has 2 commands. 1: makes you burn for a random amount of time between 1-40 seconds. 2: make yourself burn for 5 seconds. At the moment the burn works but it's only for 1 tick. This is all the code I have and I do not know how to make the burn last longer/make it random. Anyone able to help?

Code:

public class Turtles extends JavaPlugin implements Listener
{
    Logger myPluginLogger = Bukkit.getLogger();
    @Override
    public void onEnable()
    {
    }
    @Override
    public void onDisable()
    {
    }
    public boolean onCommand(CommandSender theSender, Command cmd, String commandLabel, String[] args)
    {
        Player player = (Player) theSender;
      
        if(commandLabel.equalsIgnoreCase("rburn"))
        {
            if(args.length == 0)
            {
                int randomFireNumber = (int) (Math.random() * 40);
                player.setFireTicks(randomFireNumber);
                player.sendMessage(ChatColor.GOLD + "You have been set on " + ChatColor.RED + " fire " + ChatColor.GOLD + " for " + ChatColor.AQUA + randomFireNumber + ChatColor.GOLD + " seconds!");
            }
          
            else {
                player.sendMessage(ChatColor.RED + "Invalid arguments, try /rburn");
            }
        }
              
      
        else if(commandLabel.equalsIgnoreCase("burn"))
        {
            if(args.length == 0)
            {
                player.setFireTicks(20);
                player.sendMessage(ChatColor.GOLD + "You have been set on " + ChatColor.RED + " fire!");
            }
            else {
            player.sendMessage(ChatColor.RED + "Invalid arguments!");
            }
        }
        else {
            player.sendMessage("Unknown command, try /burn");
            }
        return true;
    }
  
}

 

1 second = 20 ticks
Burning for 1 to 40 ticks = 0.05 to 2 seconds
Maybe that's going wrong?

 

Ohh Ima check that out tomorrow, thx!