Ultimate Gutenberg Addon – buttons issue

I use the “Ultimate Gutenberg Blocks Addon” for several items on my page. But when I use the “Multi BUttons” on an event, it’s content is rendered twice (partially):

<div class="wp-block-uagb-buttons-child uagb-buttons__outer-wrap uagb-block-65b79b21">
<div class="uagb-button__wrapper"><a class="uagb-buttons-repeater" href="https://www.dfbv.de/sport/deutsche-meisterschaften/anmeldung-zur-dm-feld-und-jagd/" rel="noopener noreferrer" target="_blank"><p></p>
<div class="uagb-button__link">Anmeldung</div>
</a><p><a class="uagb-buttons-repeater" href="https://www.dfbv.de/sport/deutsche-meisterschaften/anmeldung-zur-dm-feld-und-jagd/" rel="noopener noreferrer" target="_blank"></a></p></div>
</div>

If I use the buttons on a page or post of the same site, they work perfectly.

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