Check last year's Virginia income tax return. Your 2021 Income Tax Liability After Spouse Tax Adjustment and Tax Credits is line 1 of your 2021 Form 760C.
If you used TurboTax to file your 2021 Virginia tax return see "How do I view, download, or print a prior-year return?" If you used another tax service, a tax preparation company or an accountant, check your records or contact them.