Hello Sadaf, bihar NEET has cancelled the first round of counselling and admision. Fresh dates have been released for choice filling, and you have to fillup your choice entries once again however you do not need to register once again since the counselling process is only available to already registered students.

Check out this news article for detailed info on new schedule: https://www.indiatoday.in/education-today/notification/story/bihar-neet-first-online-counselling-cancelled-check-revised-time-schedule-for-ug-admission-here-1572162-2019-07-22