You may have to start a 2020 tax return before the links on the Tax Home web page become available. In that case start the 2020 tax return with the User ID you used for the 2019 return. Once some basic information has been transferred over, Tax Home should be visible on the left column. Click on Tax Home and then the other links will be shown as in this screenshot.
To access your current or prior year online tax returns sign onto the TurboTax website with the User ID you used to create the account - https://myturbotax.intuit.com/
Scroll down to the bottom of the screen and on the section Your tax returns & documents click on Show. Click on the Year and Click on Download/print return (PDF)
Use this website to contact TurboTax support during business hours - https://support.turbotax.intuit.com/contact/
Use this phone number and select TurboTax - 1-800-4-INTUIT (1-800-446-8848)
On every TurboTax web page, including this one, scroll down to the bottom of the page and click on Contact Us
Or you may have another account. It's common to end up with multiple accounts. First LOG OUT of whatever TurboTax account you're logged into right now. Then use this TurboTax account recovery website to get a list of user ID's for an email address. Run the tool against any email addresses you may have used
If you used the Desktop CD/Download program then the only copy is on your computer and not saved or stored online.
You can also request a transcript from the IRS