Hello Student

Even you have not.got OTP in your mobile phone or through email ID then you have to take an action as to inform to the authority of NTA. Ye to maid and request application to the authority of NDA stating your problem reach your facing regarding not receiving OTP in your mobile or mail ID , with the requisite group of application form and valid documents a posted with your application as soon as possible. Hoping that you will get receive OTP from the official authority of NTA as an urgent. In both other cases authority respond positively and act to solve the problem at an urgent basis as there is a question of registration of your application.

Hope this will help