The thing is candidates who have joined round-1 seat and resign before round will be elgible for mopup round. Candidates who are not upgraded in round-2 and resign their seat of round-1 within two days of publication of the result of round-2 will be elgible for mop up round of  PG Counselling 2020. So there is no new registration in round-2.

Hope helps this for you!!!

All The Best.