Some rejected returns can be fixed and re-filed. Some have “un-fixable” reasons for the rejection and have to be mailed instead.
You received a rejection email that we cannot see. Please tell us word for word what it says so we know how to help you. Or even copy and paste the email message.
If you used the IRS non-filer site to get a stimulus check, you will now get a “duplicate SSN” rejection. We are seeing people who did not notice or ignored the warning on that site about using it if they would be filing a tax return.
https://ttlc.intuit.com/community/tax-topics/help/stimulus-how-to-file-your-return-after-getting-reject-r0000-902-01/01/1602609