Context menus disappearing

Is anyone else experiencing that the property bar will not be appropriate to the object? I am seeing it in circles, mainly, after the drawing as been open for an hour or so and there are a good many objects. I will make or paste a new circle and the property bar will not show the properties belonging to circles. If I want to make an arc, for instance, the arc option doesn't show in the property bar or properties box. I've tried reselecting, deselecting, selecting something else and coming back.... The only thing that seems to work is to save the drawing, close the program and reopen it.