You should not amend, you should send the IRS the information they requested in the letter. You can state you incorrectly entered the wrong amount that you paid, then included how much you paid along with proof on what you paid. Once the IRS receives the information they requested they will adjust your return & then process your return.
On your return in your account you can just correct the amount, don't amend. You can undo the amended return.How do I cancel or undo an amended return in TurboTax Online?