Hello there,

Yes will be eligible to participate in the next round of counselling.

You dont need to register or pay agail as you are already registered.

Choices submitted by you in round-1 will be nullified, so you have to submit new choices .

Read this article for more info- https://medicine.careers360.com/articles/neet-counselling

Feel free to ask about any query in the comment below.

Hope it helps :)