If you do not itemize deductions, on the federal return, you do not need to correct it.
If you do usually claim the state and local income tax deduction, on Schedule A, of your federal return, you have some choices.
Since you actually paid it, in 2018, you are still allowed to deduct it. But, you may have to handle the refund, received in 2019 as taxable income. You could take the attitude that the VA refund is off set by the 2018 balance due you will pay DC, in 2019 and do nothing.
With TurboTax (TT) on-line software, there is no way to correct it. You'll have to use a convoluted work around.
For download (desktop) software, see the following link for how to handle. https://ttlc.intuit.com/community/state-taxes/discussion/excess-state-income-tax-withheld-for-2017-i...
