I'm new to PTO and just purchased 2020 software. I have potential client who needs me to do their 2017 and 2018 return. They self-prepared 2019 return already. When I tried to access 2017/2018 it gave me this message:

Purchase tax year 2019 returns to continue.
In order to access or create requests for previous tax years, you’ll need to have at least one tax year 2019 return in your account. If you think you reached this page by accident, please try again later.

I don't need 2019. What should I do? TIA