NO
See this from the IRS https://www.irs.gov/newsroom/irs-to-recalculate-taxes-on-unemployment-benefits-refunds-to-start-i
Was your federal return ever accepted? If not, you just need to file your federal return as it has not been filed yet.
See the link below to determine if your federal return was accepted as originally filed.
How to check your e-file status
If it was accepted, you do not need to do anything if you are only amending for the unemployment benefit change that occurred during the tax season. The IRS will automatically be issuing refunds based upon the amounts reported on your tax return as filed.
Both federal and Missouri were originally accepted.
When I amended Missouri, the federal came back as rejected. I guess I didn't realize I was amending both?
But, it sounds like I do not need to worry about the federal amendment (even though it was rejected). I could not E-file for Missouri.
No, you don't need to worry and it sounds like your original returns were filed and accepted.
As such, you don't need to amend your federal return since the IRS will automatically be making the adjustments and issuing refunds for the unemployment income that is no longer taxable.