Did you send the check in with a 1040ES slip? Thatis an estimated payment for next year 2018. A 2017 tax due would be on a 1040V voucher. Sounds like you sent in the wrong slip. So you will need to remember it and enter it into next year’s return. Don’t forget.
Or when you paid with a credit card or EFT did you select the wrong type of payment? Maybe you picked to apply it to 2018 because you were paying it now in 2018? Were they for the same amount? If not be sure to enter the right amount next year for the estimated payment.
