You can reach out to them at: neet @ nta .ac.in  from your Registered Email Id. But there are 2 things to it. If you made a error int he application form and it appeared the same way in the Admit card, then NTA will not make the correction because the Information Bulletin states taht neither will NTA accept requests for changes in the application form once the correction window has been closed nor will NTA make the changes on your behalf. But on the other side, if you entered the details correct but they were printed wrong on the admit card, then mailing NTA will help. Eitehrways, please reach out to them at the Registered Email id