thumbnails not showing

Hi,
I am trying to:
1. Add a slideshow to this post and when you click to see images in lightbox – the thumbnails below don’t show (as showen here: https://www.imagely.com/docs/albums-vs-galleries/images/galleries/Landscapes-2#gallery/6dacbfe671d3e1e3b272937cb69ed23c/741)
2. When I change the image sizes on the settings, they don’t change

Looking forward to hearing from you! Thanks

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