Trouble adding faces in Mac Photos app 7.0

I have trouble manually adding faces to photos (when Photos app doesn't detect the face). I add the "face circle" and it appears in the center of the photo. The problem occurs when I attempt to move the face circle to the correct location. It nearly always "jumps back" to the center of the photo. I try to move it back and usually jumps back to the center. Eventually it will stay in the proper location, but may take many attempts. Sometimes I give up and move to another photo, then return to find the circle has moved to the correct location.

I doubt if anyone has a solution to this, but I am concerned that this may be due to a corruption to my library, or if this is simply a common issue that others are experiencing. I have experienced this issue for several years to a lesser degree, but recently has become much worse and makes adding faces a nearly futile exercise.

Any thoughts?