Both Fearure Image & Block Element Page Hero is showing

Hi there,

that option only disables the default themes Featured Image on a single post.
It won't apply to archives or any other Block Element that is displaying the featured image.

is this setting causing the issue?
https://imgur.com/a/msBpxeg

I am not sure what you're trying to achieve.
But if you're displaying a Header Element and a Block Element then yes thats probably the issue - delete the one you don't require.