transitioning from PC to Mac

I originally downloaded Sims4 on my PC through steam, and once that broke I bought a MacBook then redownloaded Sims on it. The only problem is that I can't transfer mine acts/kits. I'm using the same account and I just transferred my steam account onto EA. I already tried downloading it on steam but it won't allow me to. I think it's because it was originally downloaded on PC/Windows? I have like ten different packs and kits and I don't want to re-spend that money. Has anyone figured this out and how to get your packs/kits back? if so PLEASE let me know </3