Content gone since update

Under the header “ONZE LEDEN OVER DE VERENIGING:” I have 2 sliders that run simultaneously, one with pictures and one with text.
Since the last update to 2.3.32, the pictures have gone. When I insert them again and update the slider, the pictures disappear again. Both in the editor and on the page.
In the other slider, the texts are still there on the page, but they have gone in the editor.

The page I need help with: [log in to see the link]