Dear Student,

As you have cancelled your seat through the online mode then there is no chance that you can get that seat again, because the university will not accept your documents because you are out of the counselling because you have cancelled your seat.

Now you can ask to the college management to return your document, this will take some time but they will return your documents and if still you want that college then you can take admission through management quota if the college is private.

Good Luck :)