I have developed an app, using Ionic Framework with React, running on top of Capacitor. Now I have to implement Push Notifications on Android and iOS, but I'm requested to not use third parties such as Firebase. It's not my decision!

Example: A part of my app is showing Sale History of the user. I would like to have a push notification, every time a new sale is added.

How do I show Sale History in the app?

useEffect(() => {
    mounted.current = true;
    const options = {
      url: baseURL + "/sale-history",
      headers: {
        Accept: "application/json",
        "Content-Type": "application/json",
        Token: token,
      },
    };
    
    Http.request({ ...options, method: "GET" })
      .then((response) => {
        if (mounted.current) {
          setSaleEntries(response.data);
        }
      })
      .catch((error) => {
        console.log("Error in sale history");
      });
    return () => {
      mounted.current = false;
    };
  }, []);

Do you have any idea how can I implement Push notifications without third parties, for example in a static way?