@Furby Furby, as I believe has been explained to you already, please don't leave such a large gap between the bottom of the chin and the bottom of the cut. You need to nudge the collar upwards before cropping the original image.

Since in some sources, like probably this one, the person in the image may have a longer neck than usual, this would be quite difficult to achieve naturally. This video displays a simple technique of how to cut close to the chin and still display a bit of the collar: