Need help to Fix Combat bug

https://giphy.com/gifs/xUA7aOclMfGMAGauMo
hey guys im using Mistex i fixed some dupes and bugs but theres a big bug in combat

If I want to attack the player from a distance and then clicks he does not go to the player out I stand directly in front of the opponent then he is attacked. And sometimes he goes back then until the client hangs up I am helpless please help me heres the error code in the eclipse COnsole

java.lang.NullPointerException
	at org.mistex.game.world.clip.region.Region.getClipping(Region.java:372)
	at org.mistex.game.world.PathFinder.findRoute(PathFinder.java:58)
	at org.mistex.game.world.player.PlayerAssistant.playerWalk(PlayerAssistant.java:1950)
	at org.mistex.game.world.player.PlayerAssistant.followPlayer(PlayerAssistant.java:1908)
	at org.mistex.game.world.player.Client.process(Client.java:1110)
	at org.mistex.game.world.World.process(World.java:166)
	at org.mistex.game.Mistex$3.execute(Mistex.java:245)
	at org.mistex.game.world.task.Task.tick(Task.java:118)
	at org.mistex.game.world.task.TaskScheduler.run(TaskScheduler.java:101)
	at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
	at java.util.concurrent.FutureTask.runAndReset(Unknown Source)
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(Unknown Source)
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
	at java.lang.Thread.run(Unknown Source)