Please cross check your email id again and match it with your email id where you have got all notification of BITSAT, try to signup again if still problem exists contact with official they will help you out.

All the very best and good luck.

Hello Nitesh! Please check the email id you have entered once again and if the problem still persists either contact the help and support center, the details for which are given on the official website, or you can create another email id and enter that. Hope this helps.