What? You do not amend a rejected return. If it rejected it was never filed. You just fix it and resend it. Or print and mail the original return. The IRS won't know what to do with an amended 1040X return since they didn't get the first return. They will probably mail it back to you. And it's taking them 6 months or more this year to process amended returns.
Seems like you still need to file the original return.
