Hello Aspirant,

Yes, you need to visit the reporting center for this case.Candidates who were allotted and reported a seat in Round 1 and wish to change Float option to Freeze or Slide or Slide to Freeze may visit the same reporting center where they had reported earlier with a new undertaking (available with Reporting center). They must carry copies of Confirmation of document verification, Round 2 allotment letter and JEE(Main) Admit Card. 

Therefore, you only need to report at the reporting center if you want to freeze your choice. But if you have opted for float or slide ur seat will automatically keep upgrading in upcoming rounds, the seat you get in last counseling will automatically be frozen and you need not go again at the reporting center

Good luck.