Sir, its time of chhath rush. So, trains for bihar packed in just 2 mins. If you want confirm ticket try PRS on some small station or say your relatives on there. If you are first on queue its not necessary you can get the confirm ticket. Also, try middle station quota, there are chances. Or, as suggested by Pp Sir, try ticket up to ALD.after that you have an option to reach PNBE easily.