I can’t download a previous tax return? Why?

What/where is the roadblock?

Was it prepared in Online TurboTax or desktop software (CD/download)?

Have you located a prior-year online return, but when you try to download/print, is access locked, and it asks you to pay?    If so, we can tell you what all you need to do to unlock it.

Have you already filed a 2018 online TurboTax return, or is it still in preparation?

Is the prior return in the same account as 2018?

You appear to be using Live Basic, which is 79.99 for a Federal return and 34.99 for a state return.   That product has live help from a CPA/EA tax expert during preparation, and they will also review your return prior to filing.