Last week Xcode updated itself automatically and then this problem occurs. There was not any problem before this update. I think this will be a bug because nothing changed on the app side.
The interesting part of this, widgets working well on real devices but looks messy in the emulator.
You can understand what I mean with this ss:
https://stackoverflow.com/questions/64676718/xcode-12-1-emulator-doesnt-show-widgets-properly-how-can-i-fix-it