Is it necessary to register for 2 round counselling after register for 1 round
No, it is not require to register and pay again for participating in second round of online counselling in NEET 2019 if already registered and paid for first round and new choice filling will be required as choice in first will be considered as null and void.
However, if a candidate didn't registered for 1st round then he/she will have to newly register themself for participating in 2nd round.
Hope this helps you.
NEET 2020 online preparation
Crack NEET 2020 with NEET Online Preparation Program, If you Do Not Qualify- Get 100% MONEY BACK