Happy at Home Stuff Gone - New PC

Hey,

For the Happy at Home event I logged in everyday I could and had unlocked everything. I have since gotten a new PC, purchased some expansions and other packs that I've been wanting, logged in and all my unlocked items from that event are gone! I thought they would be unlocked to my account but now I'm wondering if they were just unlocked to that PC. 

How can I get this stuff back? 😭

Thanks!