Dear Zara, unfortunately AIIMS final registration process has no correction window. If you have made the payment you technically sealed the data you entered in the application.  But because you haven't clicked on 'Submit' yet, you should be able to edit the details. But with technical issues being reported, may be you not able to edit the information is one amongst them. Try clearing the cache, browsing history, restart and relogin and then try changing the information. But the relief is that you will still be allowed for the exam. And this cannot held against you during counselling because by then they will only need your documents which prove that you have passed your 10+2 and you can show your 10+2 marks list. So dont panic.