Unfortunately its not possible as far as I know. Online info cannot be changed once submitted. But you can use the typewriter feature of foxit reader to make changes to the pdf you saved for printing and attach an application mentioning the reason. Or try contacting them so that they'll reset you ID and then you can start afresh.

itsEngineer (Masood) You mentioned in another thread that your final percentage comes to a second division so is it possible that HEC will accept your application beacuse they've clearly mentioned that final degr. must be 1st div.? All the best.