Shop Isle Slider configuration no longer able to change

Ok so a few topics were raised around this already before – but all are closed without proper response. For example this one: https://www.ads-software.com/support/topic/the-last-version-of-shop-isle-theme-slider-and-banner-section-not-working/

Issue description: Having previously configured 6 sliders through the “customizer” > Frontpage sections (in dutch “Voorpagina secties”) > Slider section -> It shows the actual six slides represented as the bars mentioning “Add new slide”.

Updating and deleting does not work
However, trying to change by clicking on the top bar “Add new slide”, therewith opening up the menu where you can upload an image, add title, sub-title, button link and button label – It basically does NOTHING to the “published” button which is at the top. It is as if it does not recognize any changes are being made.

Adding does not work
Second, clicking the button below the 6 bars called “add new field” (dutch: Voeg een nieuw veld toe) –> same behaviour: Nothing is happening.

Basically i’m stuck with the 6 sliders i have configured, i cannot remove, change or add anything.

Please help

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