How do you manually reposition faces in Mac OS X Yosemite's Photos App?

I'm not sure if this is a bug or just me missing something out, but when I try to manually add faces in my Photos app (go to photo, 'Get info', 'Add face'), a circle appears where I can name/tag the face.

When I go to drag it, however, it will not let me.

I have tried right-clicking and using all of my Ctrl, alt, cmd and shift keys. It will not let me drag the circle. The only thing I can do is name it, rename it or click the cross to delete it.

Again, I'm not sure if this is an actual bug or if I'm doing something wrong. But like this, all I can do is add circles that will pop up in random places of the photo.

No clue how to fix this, please help. Thanks in advance!

Drag anywhere in the circle to move the selection area & use the dot on the right to resize.
X on the left to cancel.

This answer in the Apple Discussions/Communities suggests that this behavior (inability to move the naming circle) is a bug in Photos; to remedy it requires restarting the Photos app (which may not be as easy as just quitting and then double-clicking the app icon, perhaps requiring a system reboot).

After just experiencing this problem with Photos version 1.5 running on El Capitan (MacOS 10.11.6), rebooting worked to clear it for me.