Files and Folders permission of App keeps denied, even from Settings.

Hi Apple Engineer,

My app is using ImageCaptureCore framework to communicate to external DSLR Camera. When I connect my device to a camera, I execute the requestContentsAuthorization(completion:) to request for Access Files on Connected Cameras. This is the dialog when the request is executed:

When I tap "OK", the status of content authorization keeps "Denied". even when I open "Files and Folders" permission in "Privacy & Security" Settings.

When I switched ON the permission, the switch keeps back to turned off. You could see the reproduce in this GoogleDrive video https://drive.google.com/file/d/15B-R5TONgMWg8qFiYUGK0hTy62dsVGUX/view?usp=sharing

The occurrence keeps happen even:

1. I uninstall and install the app back
2. Do "Reset Location & Privacy"
3. Do "Reset All Settings"

I attached the sysdiagnose files in this GoogleDrive file https://drive.google.com/file/d/11lovl_xC95AKXQTkZ1_e6UbEgS5md0Z3/view?usp=sharing

I firstly experience this issue after researching ImageCaptureCore's API. I executed resetContentsAuthorizationWithCompletion:. After that, my permission request keeps denied as described above :(

There are other developer that experiences the same as mine https://forums.developer.apple.com/forums/thread/756960 . There is a simple sample project there and it's reproducible in my case.

Could you help me how to accomplished my app can be granted for permission to "Files and Folders" permission when using ImageCaptureCore? Could it be a bug from the system?