in filling of nda exam my signature was upload downword and form was fill. what can i do?

I think you are telling that your signature which you uploaded was uploaded in reverse rotation. If that is so then you have to reapply because there is no other option to change that. You will have to reapply and the form is still available. If you don't your form can be cancelled as well in future if not it will create a problem. So better adviced is reapply.