Facebook share image

You would have to add an image to the page/article wherein you put the Petition.
If the image still is not displayed properly on Facebook, you might consider using a Plugin like SSO free to add the needed tags for Facebook. But it is possible, that your theme already contains the necessary coding.

https://www.freinetvilvoorde.be
There’s an image on the page (top section), that one is not taken.

Tx

Is this sorted out now?

Haven’t heard back, marking this as resolved