Tiktok unliking things that I’ve liked

My girlfriend and I were cuddling and while she was using my phone, she went on to tiktok and check her profile and to my surprise, her vids that I liked were unliked, which was weird because I remember liking them - I always like her videos everytime I see a notification from her on my friends’ feed.

Is there a fix for this? Also, anyone know why I dont see her reposts on my fyp? I have to go to her profile to see the stuff she reposts whereas she sees my reposts on her fyp.