react progressive web app offline mode not working

i am trying to make offline mode for my react app. i store data in cache and trying to restore it when there is no network but i dont know what is the issus and i am unable to load it here is my code kindly have a look and let me know . thanks in advance.

//for storing in cache 

let cacheData = "appV1";
this.addEventListener("install", (event) => {
  event.waitUntil(
    caches.open(cacheData).then((cache) => {
      cache.addAll([
        "/static/js/main.chunk.js",
        "/static/js/0.chunk.js",
        "/static/js/bundle.js",
        "/static/css/main.chunk.css",
        "/index.html",
        "/",
      ]);
    })
  );
});

//for restoring from cache in Offline mode

this.addEventListener("fetch", (event) => {
  console.log("caches", caches);
  event.respondWith(
    caches.match(event.request).then((resp) => {
      if (resp) {
        return resp;
      }
    })
  );
});