Dear aspirant

If your registration process have been completed in first round and missed choice filling then don't worry you will get chance to fill your choices and lock it in round 2. As bihar first round admission process is still going on so once it will complete you will get chance to fill your choice and lock it in round 2. You can check various counseling event details of Bihar neet UG counseling from the link below

https://www.google.com/amp/s/medicine.careers360.com/articles/bihar-mbbs-counselling/amp

hope this information helps you

All the best !!