She needs to bend over the chair in the other direction. Like this:
Now you can have an unimpeded swing at her bottom. In the top shot this would have been impossible because of the chair back. Placing a naughty girl in the correct position for her punishment is a skill that requires patience and determination. We all know you want to get to work on that bottom as soon as you have said “bend over.” But if you pause for a moment and consider the maximum impact and pleasure (yes pleasure, we can discuss that in another post) for her, then consider the arch of your arm and any obstacles in the way.
Once you have her in the perfect position then you can spank her until both of you are fully satisfied.