Yes, enter 0 as the cost basis and click The cost basis is missing or incorrect. The next screen will ask you to adjust the cost basis, if it is reported in the transaction supplement, you can click the I found my adjusted cost basis and enter the cost basis there. This will ensure you are not double-taxed on your vested RSUs. If you did not sell all the shares that vested, make sure you keep that supplemental information in case you need the cost basis again in a later year.
