Said I registered a vehicle last year when I actually did it the year prior

[LynnN82]

If the wrong information has been entered, simply got to the "Search" box, enter 'vehicle registration' then click on the "jump to" link when it appears. you will go to Federal Taxes, Deductions & Credits, cars and other things you own, car registration fees. simply correct the amount.

Such errors, or apparent errors, are fairly common around year-end. You should simply claim the tax benefit in the proper year, and keep the paperwork in case your return is examined.

[underdog427]

Sadly I realized it after submitting everything so I have no option to go back to anything that I can find. 

[DanaB27]

If you have already submitted your return then you will need to see if your return gets accepted or rejected. Please be aware that the IRS currently won't start processing returns until February 12, 2021.

• If your return will be rejected by the IRS, then all you have to do is make the changes on your return and refile.

• If your return will be accepted by the IRS,  then you have to file an amended return (1040X) to make changes. But you might want to wait until your refund or payment is processed. Please be aware that you can e-file your 2020 amended federal tax return, but most states require amendments to be printed and filed by mail.

 Please see FAQ How to amend a tax return for instructions.