Hello Aritra,
Sorry for the delay,
Here is the official website of NIH Kolkata for help,
http://www.nih.nic.in/
After examining the NIH Kolkata counseling 2018-19,
these are the important dates:
Round 1st
Round 2nd
MOP-UP Round for Central/Deemed University/National Institutes only
All India Online counselling will start from June 25, 2019.
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