hello donapativigneshwar,

You dont need to worry for thet if in such canse a candidate forgot his or her application number that is your hall ticket number , candidate can get back from the official website of the college only just log in from your email id and  then click forgot and follow teh process you will get back your application number and as evry candidaet who register on vit for the application form has tehir log in and password so that the candidate can handel their details and get the information regarding the admisson.

if you still face any issue or problem feel free to ask in comment section below. all the very best have a great future ahead.