Problem adding Place names

I'm having a problem adding new place names for my US photo locations. Each time I try to add a new city it creates another 'path' listing: for instance United States, Florida, Miami instead of simply inserting Miami to the current United States Florida listing. It doesn't make any sense to me. I don't want to have multiple United States entries under Places on the right side of the page for each new city or state that I add for a location. Has anyone else run into or dealt with this same problem? I wish I could describe it better. Any assistance in how I can resolve it will be greatly appreciated. Thanks very much.