Hey Srinisha, 

The NEET Mop Up Round is, basically, the last and final round of NEET UG Counselling. It is conducted after the NEET UG 2nd Round of Counselling is over and seats are left. In order to fill up the vacant seats, the Mop Up Round is conducted. The Mop Up Round is conducted to fill up the seats left vacant in Central and Deemed Universities.

At the time of registration students have to pay some fee, which is as follows. 

For Deemed Universities   Non Refundable Registration fee :- Rs. 5000/-Refundable Security amount:- Rs. 2,00,000/-

Refundable fee is settled at the time of admission in universities as the fee.