How to tansfer 2019 PDF file created by TurboTax to 2020 TurboTax

My .tax2019 file for the 2019 return created by TurboTax Premier is missing from my computer (PC with Windows 10), but the PDF file is intact. I noted instructions to use the Zamzar website to convert the PDF file to TXF format which could be read by TurboTax. Howeve, there is no TXF format to convert to on the Zamzar website. Will appreciate any guidance on how to convert the PDF file to a TAX file for TurboTax.