If you have previously filed the tax return where the original W-2 was reported, then you will have to file an amended tax return, Form 1040X, to report the corrected W-2.
See this TurboTax support FAQ for amending a prior year tax return originally completed and filed using TurboTax - https://ttlc.intuit.com/questions/1894381-how-to-amend-change-or-correct-a-return-you-already-filed
