EA app can't repair the sims 4 game

Because you added it on steam you can now only repair the game on steam. So, your solution should be that you reinstall the game on steam and then your DLC should be downloaded again with EA APP (You need to start EA APP manual because EA APP open and close itself if you start/close sims 4 via steam, at last it is my experience)

I have the same problem with the app on this old account, I can’t repair the game via EA app anymore because it required on my steam account, only with the problem that I unlinked my steam account, and the EA APP/ Account-Setting don’t recognize this step. (EA Support was no help with my issue and I would have given up on sims if my other half not surprise me with the whole sims4 collection again on my new steam / EA Account)

//To the DLCs; was worked for me was to start sims 4 via shortcut so I could avoid the *required* steam and it would start my copy from EA and not from steam. Origin added two copys to your library one from steam and on from EA, because of this, this issue is not existent there. EA APP only has one copy from games, and this causes all funny things + errors.