Anyone know how to get your TT desktop file into the live online version?

I bought the TT online version from Costco and activated it. It said it failed to upload my pdf of last year TT desktop file when I asked it to do that. It would seem like taking that first step of uploading last year taxes would be easy thru TT, but it wouldn't let me. I talked to someone who told me to take some further steps that then meant I couldn't go back and clear and start over, which I could have done at the page I was when I started talking to her. So now I'm stuck and can't start over, have paid $175 for this, and can't upload my 2019 file. She also told me that I could always do it later in the program, but that's a lie because now if I try to do it, it tells me that I can't because I've activated it. So has anyone else found a way to upload a desktop pdf 2019 file into your taxes once you started them? I spent over 2 hours today on the phone with the first person who steered me VERY wrong, then with a second person who was trying to help when I had to get off because of a doctor's appointment commitment (I hadn't expected it to take this long when I asked for call) and then that person said she'd call me back in an hour and now, 4 hours later, no phone call. I'm off to a very negative start with TT this year...