Circle marking a face in Photo cannot be moved

Hello,

Since today, when adding a new face to to a photo, I cannot move that circle from the picture's midpoint onto the person's face any more. In fact, the only function that still works is the "X" at the left side of the circle, deleting the circle. The right markt to scale the size of the circle up and down no longer works, nor can I click on the circle's edge and move it around. Instead, every time I click on the circle, a miniature picture of the entire picture is shown, which I can move onto my desktop which causes the picture to be copied onto the desktop.

Does anyone experience the same problem and has figured out a solution?

Thanks!