Hello smitha

Now you can not make changes in your neet application form . It's too late now . Neet correction  window period is over. It was for hhree days march 18, 2024 to march 20 , 2024 till 11.59 pm .

You may send a mail to the official website but I don't think at this time they Will help you . The exam date is coming  closer .

As a few days are left for neet exam so you also must focus in neet preparations.  Whatever it is Let it be for now.

surname is in expanded form and not in correct right ?

You can do one thing , at the time of counseling you must carry your father's  ID or any document in which surname is entered .

It's nit a big error . If there is mistake or unacceptable you would have got message from the examination authorities so do not worry and pay attention to neet preps.

All the best .