I called the Apple Support and we will wait until Wednesday.
Apple support told me it's a brand new device and there is a chance that the issue solves when I used it for a few day. When the white to yellow gradient is still visible next week then the iPhone XS Max will be swapped with a new one.
Apple support told me it's a brand new device and there is a chance that the issue solves when I used it for a few day. When the white to yellow gradient is still visible next week then the iPhone XS Max will be swapped with a new one.