Broken link to thumbnail with nextgen gallery

Hi,
I have a page where I display an album with 2 galleries and for each gallery there is a thumbnail linking to it.
My problem is that for one of the gallery the image is shown and not fot the other.

For the one working the link is like that /wp-content/gallery/perth/dynamic/WP_20141024_002.jpg-nggid014-ngg0dyn-91×68-00f0w010c011r110f110r010t010.jpg

For the broken one the link is like that /nextgen-image/193/91×68/crop/9378e176c6595302ef8f143549a62048

I have no idea why it’s different as both galleries are configured the same way from what I see.

The link to the album in the page is like this :
<img class=”ngg_displayed_gallery mceItem” src=”https://www.oneyearinoz.be/nextgen-attach_to_post/preview/id–33&#8243; alt=”” />

Any help would be appreciated…
My issue is in this page if it can help you find the root cause :
https://www.oneyearinoz.be/photos/