Tiktok can't connect to wifi (it works just fine with everything else)

So, my mom's tiktok stopped working weeks ago, she's been using it for quite a while (without an account) just fine until now.

I have no idea what else to try anymore, so far I've tried:

The classics: Turn off/on phone, turn off/on wi-fi, forget and put wi-fi again, use the phone's internet, nothing.

Re-installed, restart, router restart, pretty much everything. The phone is an iPhone 8 Plus.

Are there any solution or people that had this before?

The "Explore" page works. "Following" and "For you" page does not. Search bar results also doesn't work. Can enter settings just fine. And yes, tiktok is allowed on my region.

So... Yeh.