Hope this reference helps - https://www.creditkarma.com/tax/i/irs-rejects-tax-return#:~:text=If%20you%20are%20mailing%20a,it%20back%20to%20the%20IRS.
Quote from the same article - "Don’t worry if you filed your return by the due date and it gets rejected. The IRS will consider it filed on time if you make the necessary corrections and e-file it again within 10 days. If you are mailing a paper return, you have until the actual due date of the return (generally April 15) or 10 calendar days after the IRS gives notification that the return was rejected or that the return cannot be accepted for processing, whichever is later, to get it back to the IRS. You should include an explanation with the paper return."