I had one over the weekend and another preparer posted they had one too.  Mine was corporate, his was individual.  We notified ProSeries. We also both found a link to do 6 steps to resolve and they didn't work. I found that if a prior client and I retransferred the file to 2020 it worked.  Other alternative, start a new file. It's a pain but we probably won't get an answer anytime soon.