okay, i will try to explain…
Responsive images size the height by the width.
Your origional image is 808 x 2000 or roughly .404:1`
Your image is getting sized to 304 x 752 (also .404:1)
You need roughly 1100 pixels of height for that area so you need to start with an image that is roughly 445x1100
in other words, you don’t have enough width to get that height in the same aspect ratio (without distorting the image)