Error Message in Backand, 404 under event

Hi, in Backand in the area „Events“ i have on the right side this error.

https://ibb.co/spRsWXXJ

also in frontend after every event i have a 404

window._wpemojiSettings = {“baseUrl”:”https:\/\/s.w.org\/images\/core\/emoji\/13.1.0\/72×72\/”,”ext”:”.png”,”svgUrl”:”https:\/\/s.w.org\/images\/core\/emoji\/13.1.0\/svg\/”,”svgExt”:”.svg”,”source”:{“concatemoji”:”https:\/\/ffw-bad-bergzabern.de\/wp-includes\/js\/wp-emoji-release.min.js?ver=5.8.2″}}; !function(e,a,t){var n,r,o,i=a.createElement(“canvas”),p=i.getContext&&i.getContext(“2d”);function s(e,t){var a=String.fromCharCode;p.clearRect(0,0,i.width,i.height),p.fillText(a.apply(this,e),0,0);e=i.toDataURL();return p.clearRect(0,0,i.width,i.height),p.fillText(a.apply(this,t),0,0),e===i.toDataURL()}function c(e){var t=a.createElement(“script”);t.src=e,t.defer=t.type=”text/javascript”,a.getElementsByTagName(“head”)[0].appendChild(t)}for(o=Array(“flag”,”emoji”),t.supports={everything:!0,everythingExceptFlag:!0},r=0;r<o.length;r++)t.supports[o[r]]=function(e){if(!p||!p.fillText)return!1;switch(p.textBaseline=”top”,p.font=”600 32px Arial”,e){case”flag”:return s([127987,65039,8205,9895,65039],[127987,65039,8203,9895,65039])?!1:!s([55356,56826,55356,56819],[55356,56826,8203,55356,56819])&&!s([55356,57332,56128,56423,56128,56418,56128,56421,56128,56430,56128,56423,56128,56447],[55356,57332,8203,56128,56423,8203,56128,56418,8203,56128,56421,8203,56128,56430,8203,56128,56423,8203,56128,56447]);case”emoji”:return!s([10084,65039,8205,55357,56613],[10084,65039,8203,55357,56613])}return!1}(o[r]),t.supports.everything=t.supports.everything&&t.supports[o[r]],”flag”!==o[r]&&(t.supports.everythingExceptFlag=t.supports.everythingExceptFlag&&t.supports[o[r]]);t.supports.everythingExceptFlag=t.supports.everythingExceptFlag&&!t.supports.flag,t.DOMReady=!1,t.readyCallback=function(){t.DOMReady=!0},t.supports.everything||(n=function(){t.readyCallback()},a.addEventListener?(a.addEventListener(“DOMContentLoaded”,n,!1),e.addEventListener(“load”,n,!1)):(e.attachEvent(“onload”,n),a.attachEvent(“onreadystatechange”,function(){“complete”===a.readyState&&t.readyCallback()})),(n=t.source||{}).concatemoji?c(n.concatemoji):n.wpemoji&&n.twemoji&&(c(n.twemoji),c(n.wpemoji)))}(window,document,window._wpemojiSettings); img.wp-smiley, img.emoji { display: inline !important; border: none !important; box-shadow: none !important; height: 1em !important; width: 1em !important; margin: 0 .07em !important; vertical-align: -0.1em !important; background: none !important; padding: 0 !important; }

================ Installation Data ====================
==My Calendar:==
Version: 3.8.1
DB Version: 3.8.1
URI: https://ffw-bad-bergzabern.de/termine/
CSS: twentyeighteen.css
Requester Email: info@hosting4you.biz
Admin Email: webmaster@ffw-bad-bergzabern.de

==WordPress:==
Version: 7.1
URL: https://ffw-bad-bergzabern.de
Install: https://ffw-bad-bergzabern.de
Language: de
Charset: UTF-8

==Extra info:==
PHP Version: 8.4.24
DB Version: 10.11.18
DB UTC Offset: +02:00
WP UTC Offset: +02:00
DB Type: InnoDB
Server Software: Apache
User Agent: Mozilla/5.0 (iPad; CPU OS 26_5_2 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) CriOS/150.0.7871.113 Mobile/15E148 Safari/604.1

==Theme:==
Name: Freiwillige Feuerwehr Bad Bergzabern
URI: http://www.ffw-bad-bergzabern.de
Parent: keine
Version:

==Active Plugins:==
Advanced Editor Tools: 5.9.2; https://wordpress.org/plugins/tinymce-advanced/
Antispam Bee: 2.11.13; https://antispambee.pluginkollektiv.org/
Cachify: 2.4.2; https://cachify.pluginkollektiv.org
Classic Editor: 1.7.0; https://wordpress.org/plugins/classic-editor/
Contact Form 7: 6.1.7; https://contactform7.com/
Disable & Remove Google Fonts: 2.0.1; https://wordpress.org/plugins/disable-remove-google-fonts/
Einsatzverwaltung 2.0: 2.3; https://einsatzverwaltung.eu
Einsatzverwaltung 2.0 - letzter Einsatz: 2.2.0; https://einsatzverwaltung.eu
Gallery Carousel Without JetPack: 0.7.5; http://www.wpbeginner.com/
InfiniteWP - Client: 1.13.10; http://infinitewp.com/
My Calendar - Accessible Event Manager: 3.8.1; https://www.joedolson.com/my-calendar/
Seiten nicht in der Navigation ausgeben: 1.92; http://wordpress.org/extend/plugins/exclude-pages/
Sidebar Login: 3.0.1; http://wordpress.org/extend/plugins/sidebar-login/
Simple Page Ordering: 2.8.0; http://10up.com/plugins/simple-page-ordering-wordpress/
User Access Manager: 2.3.18; https://wordpress.org/plugins/user-access-manager/

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