Dispatch and PostX giving 2 feature images per post

Hi, I'm using the Dispatch theme. On the posts it has 4 elements - the open and close wrappers, the secondary navigation, and the single post hero. I think the single post hero is beautifully done and looks great. The main part of my posts is built with WXPRO - Postx blocks. But this creates two feature images - the single post hero with the title written over it, and a second feature image (with no text on it) below. An example is here: https://tripanthropologist.com/visiting-pompeii-and-mt-vesuvius/

Turning the 'feature image' either doesn't work at all or just removes the image from the single post hero, leaving only the text.

Could I please have help to fix this?
thanks, Monique