Service Worker save App: Event handler of 'install' event must be added on the initial evaluation of worker script

The app is not able to download. In Lighthouse I got the issue that the service worker or manifest fails.

I get two warnings, I do not understand :

1. Event handler of install event must be added on the initial evaluation of worker script.
2. Event handler of fetch event must be added on the initial evaluation of worker script.

App URLS: @Vimal Patel

Site: https://www.kuehroint.com/archenkanzel/archenkanzel-wimbachbruecke.html Service Worker .sw https://www.kuehroint.com/archenkanzel/sw.js (Warnings) Manifest Jason https://www.kuehroint.com/archenkanzel/manifest.json

This script i think is not in use. https://www.kuehroint.com/archenkanzel/service-worker.js

Console Warnings in Code Comments :

self.addEventListener('install', function(event) {
 // Perform install steps
 var CACHE_NAME = 'my-site-cache-v1';
var urlsToCache = ['archenkanzel-wimbachbruecke.html'    ,
'     ../xcss/bergtouren.css',
'../icons/kuehr.jpg' 

];

 
self.addEventListener('install', function(event) {  /*<-- Event handler of 'install' event must be added on the initial evaluation of worker script */
 // Perform install steps
 event.waitUntil(
   caches.open(CACHE_NAME)
     .then(function(cache) {
       console.log('Opened cache');
       return cache.addAll(urlsToCache);
     })
 );
});

self.addEventListener('fetch', function(event) { /*<-- Event handler of 'fetch' event must be added on the initial evaluation of worker script.*/
 event.respondWith(
   caches.match(event.request)
     .then(function(response) {
       // Cache hit - return response
       if (response) {
         return response;
       }
       return fetch(event.request);
     }
   )
 );
});
});