can I reapply CAT (with new mail id and mobile number)for some changes if my changes not be done by edit window
As per Cat rules, you can't do that as one person can do registration just once. If you did some mistakes in your form then you can apply for rectification by mailing on their official I'd. Also if you'll login you will get a option to edit details.
Moreover ,if you want to apply again then you can do that but if Cat officials caught you doing that, they will cancel both of your registrations.
I hope this information would be helpful for you.
All the best for your bright career ahead.