iPhone 16 Pro camera black screen scanning codes in apps

My camera won't work in apps where it needs to scan (QR) codes.

My iPhone 16 Pro is brand new, but won't let the camera scan any codes or information when used in a banking or transportation app after a while. The camera viewfinder just shows a black screen. It fixes itself for a bit when I restart the device, but I don't want to keep resorting to that. I am on iOS 18.7.1.

My friend has the exact same phone, but never encounters this issue. I've seen other people have had this issue as well on older builds of iOS. I have checked my settings and all the apps have access to the camera as it does occasionally work. Any help would be much appreciated!