I dont think currently there is any remidy for revision/cancellation of form 15ca filed online. Try to upload another with correct details and make the payment. Since there is no clarity yet in any guidelines older one may be useless.
I have clarified on the same with tininfo @ nsdl.co.in and my view is in line with such clarification received. Kindly let me know if the same is incorrect.
plz mail me clarification too......at desai.tarang @ icai.org
but after 1st oct 2013 we hav to e file 15ca on efilling income tax india
now what is the remedy to modify or revise 15 ca already filed at tin nsdl