What does repairing EA app do?

The EA App has been working just fine for me until today, out of the blue. I was playing Sims 4 yesterday just fine.  The App starts to load but then just disappears.  Ive gone into uninstall programs to see if i can repair but the only option i have is uninstall.  Is there another way to repair it ??? Ive rebooted my pc and tried all sorts  but nothing is working.  Searches suggest that many others have been having issues opening the App since its launch and some have found solutions and some haven't. Im guessing the bug or bugs still aren't fixed.. First time since Sims 1 i wont be able to play any more, im devastated..  ☹️  Luckily for me i only have sims on EA and the rest of my games are from Steam.  If anyone has any suggestions how to repair this it would be most appreciated.