I have been filing income tax with Quick tax since 2018. However, when i try toview previous returns, returns, it only shows files up to 2020. The rest are missing,

If you have used TurboTax Online, TurboTax automatically saves  PDF of all your returns for 7years period ( as long as you are using the same User ID), How to find previous PDF tax returns using TurboTax Online

If you have used a TurboTax Desktop Version, the back up files (.tt**) should be on the computer you had the software installed. Please note for security and privacy reasons we do not have an access to your returns. 

Thanks for choosing TurboTax.