My return was rejected and I need to make changes. The menu doesn't offer me the ability to go in and change anything. Where do I find this option?

It was rejected due to First Time Home Buyer Credit.  I need to add form 5405 but there is nowhere to go in and make changes.  I am not to amend, as they were rejected. But I can't find anywhere on the site to go in and changes and add the form.  I've already paid.