Hii
Yes, you need to do Fresh Registration for Mop up Round. Again you need to do Choice Filling/ Choice Locking but don't need to pay again.
To know more about Mop up Round, Click below link & go to (Page-4) -
https://images.careers360.mobi/sites/default/files/NEET-2018-Counselling-FAQs.pdf
All the best.
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