iPhone app in Portrait only?

I can't get my latest iPhone app to run in portrait mode only. In Xcode I've checked only the box that says "Portrait" under Device Orientation, and I've also examined the Info.plist file to ensure that there aren't any hidden settings for other orientations.

I've also tried checking or un-checking iPad, and checking "Requires Full Screen" when that option appears. No matter what I do, when I run the app on my phone and rotate the screen, the interface rotates.

What am I doing wrong?

Is the app overriding the application(_:supportedInterfaceOrientationsFor:) method in its app delegate?

iPhone app in Portrait only?
 
 
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