Accordion list – loading issue with search form

Hi,
I created a shortcode for a list view calendar with accordion design.
If I select an option in the “Ort” dropdown in the search form on the website, the events are still filtered accordingly, but a permanent loading symbol appears in the foreground, which makes the page non-functional.
This error does not occur with all other designs. Anyone know how to fix this in accordion view?
Thanks
Jakob

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