@kathydana mmmm that's a bit different than what I am experiencing. But your situation is a lot serious because you keep your internet on it seems and all your packs are missing after switching it to offline mode.
Once I log into my EA app. I turn it to offline mode and disconnect my PC laptop from any wifi so I can just keep the app on and play Sims 4 at any time of the day without needing to log in again. I did this with my origin app and it didn't have any problems what so ever and it was simplicit as just clicking the mouse. The packs I have were all showing up and when I switched over to this EA I been disappointed in it's development so far with it offline capabilities.