I'm not sure why my Premiere Pro Auto updated into 2021, and when I try to reinstall back 2019, it missing. The others version there only got version 15.0 and 14.9. So I just wondering is it possible to get back 2019 as I facing lots of trouble when using 2020 & 2021
Nope. I believe Adobe only allows a couple of versions back now. Likely your computer hardware is old and can't handle the new feature implementation and coding in the app that relies on newer hardware to work properly.
Well... that certainly is some useful information! I guess it should be noted that Adobe does not supply support anymore for those versions and I'm genuinely surprised they are even available to download. Why doesn't Adobe just supply these links themselves? Maybe Kevin can chime in.