My fat neck

Pardon my crude profile drawings but I didn’t want to include an actual pic because I’m so embarrassed.

The drawing on the left is what I’d like my neck to look like. However my neck looks more like the drawing on the right. 😞

I’m not technically overweight (5’4” and 145 pounds). And I don’t feel like my neck was always like this.

What in the world can I do to make my neck look more like the first drawing??