Express ignores response.send() call

I have a simple site:

const express = require("express");
 
const app = express();
 
app.set("view engine", "hbs");
 
app.get("/about-me", function(_, response) {
    response.render("about_me.hbs");
});
app.get("/", function (_, response) {
    response.render("index.hbs");
});
app.all(/.*/, function (_, response) { // 404 page
    response.sendStatus(404);
    response.send("<h1>404 Not Found</h1>");
}
app.listen(3000);

But when I opened http://localhost:3000/not-exist , there was "Not Foun<" text. Why it’s happening and how to fix it?

>Solution :

You can’t send two responses to a single request.

Use sendStatus or send.

If you want to control the status code when you use send, use status.