These are the major conditions for refund it depends on which round

Candidates who have been allocated a seat in Special Round 1 and failed to report to the institute within the specified deadline, he/she shall be entitled to the refund of seat acceptance fee with a deduction of Rs. 6,000.

Candidates who opt for Surrender of Seat and Participate in Round 2 and are not allocated a seat in Round 2 must note that he/ she shall be entitled to a refund of Seat Acceptance/ Participation Fee with a deduction of Rs. 6,000

After the CSAB 2nd special round, candidates who fail to join or report to the allotted institute, his/ her seat acceptance or participation fee will not be refunded.

Hope it helps...