Ishita,

Any counselling lets the candidate to have the freedom to join the seat allocation process at any round (round1 or round 2 or round3). But as per your case if we consider a situation where you didn't pay first round seat allotment fees and then it says that you are no more eligible for the second round then don't panic. Make a list of your college, talk with the authorities. I know one of my friends who became a defaulter (not this case, it was a problem of his own) and later got admitted in one of his desired private colleges. Some colleges held decentralized counselling which can be another solution. Otherwise opt for management quota where you have to pay extra money for your seat allotment(which will be done by the college itself). Hope this helps and feel free to ask in case you have anymore doubt.