My Sims4 keeps going back to startup screen and will not run.

I have been trying to get my Sims4 game to start from the EA desktop app and all it does is try to start and then go back to the startup screen.  I have played the game on Origin for 850 hours without any issues and now since EA dropped the Origin app and switched over to their app I have been unable to get the game to work.  I have completely uninstalled and reinstalled the game and cleared the computer cache yet still having the same issue.  I have opened several tech support cases and EA has yet to get me any useful information as to how to correct this issue and keeps sending me information to clear the cache and try reinstalling the game.  I have the digital version of the Sims4 and several expansion packs and addon packs but noticed that EA is not supporting the Sims4 Legacy version and this is what support with Origin had told me was needed to run Sims4 on a PC using Windows 10 and 65-bit operating system. I would appreciate any information as to how to get the game back up and running.