Hii Revathy!
You haven't mentioned the name of the website or entrance exam you are talking about. Kindly restructure the question and ask agin including the necessary information. You can tag the subject with the question or ask in the comment section.
The problem may be due to some discrepancies with the website or traffic on the page. Check you internet connection as well. Refresh the page and try few more times. Else, you can contact the helpdesk.
Hope this helps.
Good luck!