Hii aspirant..

As having allotted a college in first round of counselling and now there is no upgradation and second round then the same college will remain allotted to you through counselling. And as you told that you are interested to take admission in that college only then now you can freeze your choice in the second round of counselling and confirm your seat at the respective college which has been allotted to you.

And after freezing and confirming your choice for the college complete the further steps for admissions and report at the reporting centres and the college allotted. Once you freeze your choice then in the third round no upgradation will take place and your seat in the respective college which was being allotted to you in the previous town will be confirmed.

Hope it helps. 

Best of luck.