Hello Alok,

These days application forms of most of the entrance exams for engineering courses or for that matter any other course are filled through online mode. Thus, a correction window is provided after the last date of filling of application forms to allw for candidates to correct any mistake that they may have made while filling the application form.

As for filling the application form again, it shouldn't be possible as the to fill the application form again and it may also lead to rejection due to multiple candidature. 

If a correction window is not provided, you should try to contact them on the mail id provided or call them to get it rectified or ask for instructions on how to proceed.