Hi Aspirant,
Hope you are doing great as per the question asked by you, no you can't change your caste after college admission you even can't change your caste if you have locked the form or the correction period is over. But you can certainly mail to the required authority regarding the same.
Hope you found this answer useful.Stay motivated stay positive.
All the best!
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile