The TurboTax online editions are only for tax year 2018 and will be shutting down shortly.
See this TurboTax support FAQ for completing a prior year tax return originally started with the online editions - https://ttlc.intuit.com/community/prior-year-return/help/how-do-i-finish-a-prior-year-return-that-i-started-in-turbotax-online/00/26322