If you want the whole picture to show, it needs to stay within the original aspect ratio. If you were to force it to be taller, the image would stretch and lose quality.
I suppose you would need to upload a taller image – that way the aspect ratio could stay at what it should be, but the image would be taller.
Otherwise you have two options:
a) Increase the image height, which will cut off some of the image on the right.
b) Increase the image height and keep the width, which will stretch the image and lose the aspect ratio.