Thanks for reaching out. Have you tried resetting the settings in the camera app? Also, Try testing safe mode and see if the same symptoms still appear.
To reset the settings in the native camera app. Navigate to your camera > Click on the "Settings Icon" in the top left corner > reset settings.
Test in safe mode - Power off the phone. Then, power on the phone and when the Samsung logo appears, press and hold down the Volume Down key. If done correctly, "Safe Mode" will display on the bottom left corner of the screen. If "Safe Mode" does not appear, repeat the steps above.