Hi, I am sorry to hear you are having this experience, and can understand the frustration. The first thing to do is to inspect the device for any damages, as that can result in such display issues (especially after dropping or cracking the device). Also, inspect the device for water damage with these steps: https://www.samsung.com/us/support/troubleshooting/TSG01001077/
The next thing to try is disabling or adjusting Adaptive Brightness, which can be done via Settings > Display > switching toggle on Adaptive Brightness (if this mainly occurs on a dimmer setting, try adjusting the Brightness bar slider).
Should that not resolve it, you can try using the device in Safe Mode, which can help determine if a third-party application might be the cause. The steps to do so are here: https://www.samsung.com/us/support/answer/ANS00062983/
Finally, if those do not help, you can try wiping your device's cache partition:
Performing a wipe cache partition removes any temporary files that may be causing an issue with the device. All personal files and settings are not affected by this option.
- Ensure the device is powered off.
If the device is unresponsive/frozen, press and hold the Power button (located on the upper-left edge) for approximately 10 seconds or until the device power cycles. - Press and hold the Volume Up button (located on the upper-left edge) and the Home button (located at the bottom in the middle).
- While continuing to hold the Home and Volume Up buttons, press and hold the Power button (located on the right edge) until "RECOVERY BOOTING" appears in the upper left then release all buttons.
- Select wipe cache partition.
Utilize the Volume Up/Down buttons to highlight and the Power button to select. - Select reboot system now.
Option is highlighted, utilize the Power button to select.
Please let me know fi this helps.
