Hi .... u can use a Create shape ... or shortcut of it ... " U " in keyboard to know why its not fill !?
u will find some points didn't marked,so you can used a create shape to mark all points ... when u do that u ... this area will make a different color ...... if u wanna fill it u can use A space in your keyboard ....try and god with u
What I meant is this, you seem to have a control point that is not part of the actual shape.
Most of the time, clicking in the middle just does not make a good selection, you need to either select or un-select the points one by one with the selection tool(g) or by using a marquee or lasso tool!