What, exactly, did you purchase? The 2018 desktop version of TurboTax Deluxe?
You are not going to get your incomplete 2018 income tax return in that manner. In fact, if you used an online version of TurboTax but did not save any information prior to the switch over to the 2019 tax year, you will not be able to retrieve your partially prepared return at all; returns that have not been completed online and filed are basically purged from the system.
