I logged in to iCloud on the iPhone Settings app, but it only pops up while loading indefinitely (logging in)

Yesterday, around 9:20 to 30 PM, I got a notification on my phone to see if someone I don't know logged in to my iCloud, so I tried to change my password and log out on all devices, and then go into the iPhone 15 settings app and log in again, so it pops up in unlimited loading.

So I've tried rebooting multiple times and Wi-Fi or data connection, but it only pops up during infinite loading, how do I fix it?