As others have documented and Samsung have ignored, there's a bug in the camera software rendering it useless if you use the flash.
This is only since the UI 3.1 Update. Below are four pictures I've uploaded taken consecutively in the same conditions. All totally over exposed. Apologies I had to use my smashed up Nike trainers but they're all I had to hand which were black to highlight how bad the issue is.
Everyone with this issue needs to send a report.
Open the Samsung Members App 》Help 》Error Report 》Camera
Or click the blue plus icon in the bottom right of the app and select Error Report.