Dear Student,

You can continue to give that exam & try to reappear for JEE Mains if you wish to while studying for NIT. But it will be a whole lot of burden on you, you will have to study for the 1st year of Engineering plus your JEE Main Exam. Sort out your preferences, take some time to come to a conclusion. And make sure you ask many people about the same.

Thank You. Hope this helps.