The Counselling procedure of round 2 says that :

The candidate who exercise Choice-2,  are required to  pay the required seats for  confirmed / assigned seats in the second round. However, they cannot download the admission rules or attend the assigned university, but  wait for the second extended round. Candidates exercising Choice 2 will participate in the second extra round by retaining the seats allocated in the second round. If a better option is given, the  seat in front will be automatically canceled. Or, if any, of the options are not assigned, the sheets assigned to them in the second round will remain in the candidate.

Hope this helps,

Thank you