Dear aspirant,

If you have reported to the college that was been alloted to you in first round  and paid the required fee which was been printed on your allotment letter.

Then that college will be an optional for you to join, your seat in that college can't be alloted to anyone else further.

Later ,if you were been another college in  round 2 then it's in your hands to select any of those, either you can choose first college or second one.

If you haven't reported or paid for the college you were been alloted in round one.you can't join the college you got in round 1.you must be totally dependent on round 2 allotment.

Hope it's clear

All the best