If you have the User ID then you need to click on forgot password button available on applicant login page
Enter the user id and copy the captcha code.
You will receive the mail on the registered Email ID.
User ID will be mentioned on the confirmation page of the application form as well, in case you do not have the User ID.
It contains 8 letters starting with 'PG'

Good Luck!

I think you have only registered by filling the neet pg application form but not paid the exam fees then the registration is incomplete even if you have username and password details. Check your mail as soon after completion of the application process you will get a confirmation mail. Otherwise since the last date for applying for NEET PG exam has been ended now you should try applying for the exam next year that is in 2020.

Dear Ashish, do you mean to say that you registered for NEET PG application form but didnt pay your examination fees and all you have are only user name and password but no details in the form?