Hi aspirant,

If you are allotted seat in first round of counselling and you accept it by paying the fee and doing all the required formalities you can surely participate in the second round. In the case you have not confirmed your admission in the college you are allotted in the round 1 your seat would be stand cancelled and you cannot go back to it even if you are not allotted a seat in round to all do not like it.  But if you have confirmed your admission you can be eligible for an upgrade in the seat through the second round but in the case you do not get any upgrade in the second round your first seat will be retained.

Hope it helps!