IDoes it cause rejection to change my husband's date of birth on the extension. When I filed it correctly it rejected?

You should have received an email explaining the reason the extension was rejected. Since you filed a federal tax extension and it was rejected, you have until 11:59 PM on April 20 to resubmit or mail your extension. 

You can also get an extension by paying all or part of your federal income tax due. Choose Extension as your reason for payment. If you do this, you don't need to fill out a separate form.