"error_description": "The authorization code was not found or was already used"

I am not able to get permanent access token using code.

Docs - https://shopify.dev/apps/auth/oauth#get-a-permanent-access-token

API - POST https://holofystore.myshopify.com/admin/oauth/access_token
Body -

{
“client_id”: “abcd”,
“client_secret”: “shpss_token”,
“code”: “abcd”
}

i have created the app using this docs - https://shopify.dev/apps/getting-started/create

following this doc to get auth token - Implement authorization code grant manually

server.js

import "@babel/polyfill";
import dotenv from "dotenv";
import "isomorphic-fetch";
import createShopifyAuth, { verifyRequest } from "@shopify/koa-shopify-auth";
import Shopify, { ApiVersion } from "@shopify/shopify-api";
import Koa from "koa";
import next from "next";
import Router from "koa-router";

dotenv.config();
const port = parseInt(process.env.PORT, 10) || 8081;
const dev = process.env.NODE_ENV !== "production";
const app = next({
  dev,
});
const handle = app.getRequestHandler();

Shopify.Context.initialize({
  API_KEY: process.env.SHOPIFY_API_KEY,
  API_SECRET_KEY: process.env.SHOPIFY_API_SECRET,
  SCOPES: process.env.SCOPES.split(","),
  HOST_NAME: process.env.HOST.replace(/https:\/\//, ""),
  API_VERSION: ApiVersion.October20,
  IS_EMBEDDED_APP: true,
  // This should be replaced with your preferred storage strategy
  SESSION_STORAGE: new Shopify.Session.MemorySessionStorage(),
});

// Storing the currently active shops in memory will force them to re-login when your server restarts. You should
// persist this object in your app.
const ACTIVE_SHOPIFY_SHOPS = {};

app.prepare().then(async () => {
  const server = new Koa();
  const router = new Router();
  server.keys = [Shopify.Context.API_SECRET_KEY];
  server.use(
    createShopifyAuth({
      accessMode: "online",
      async afterAuth(ctx) {
        // Access token and shop available in ctx.state.shopify
        const { shop, accessToken, scope } = ctx.state.shopify;
        const host = ctx.query.host;
        ACTIVE_SHOPIFY_SHOPS[shop] = scope;

        const response = await Shopify.Webhooks.Registry.register({
          shop,
          accessToken,
          path: "/webhooks",
          topic: "APP_UNINSTALLED",
          webhookHandler: async (topic, shop, body) =>
            delete ACTIVE_SHOPIFY_SHOPS[shop],
        });

        if (!response.success) {
          console.log(
            `Failed to register APP_UNINSTALLED webhook: ${response.result}`
          );
        }
        console.log('ctx.state.shopify  ', ctx.state.shopify);
        console.log('ctx  ', ctx);
        // Redirect to app with shop parameter upon auth
        ctx.redirect(`/?shop=${shop}&host=${host}&accessToken=${accessToken}`);
      },
    })
  );

  const handleRequest = async (ctx) => {
    await handle(ctx.req, ctx.res);
    ctx.respond = false;
    ctx.res.statusCode = 200;
  };

  router.post("/webhooks", async (ctx) => {
    try {
      await Shopify.Webhooks.Registry.process(ctx.req, ctx.res);
      console.log(`Webhook processed, returned status code 200`, ctx);
    } catch (error) {
      console.log(`Failed to process webhook: ${error}`);
    }
  });

  router.post(
    "/graphql",
    verifyRequest({ returnHeader: true }),
    async (ctx, next) => {
      await Shopify.Utils.graphqlProxy(ctx.req, ctx.res);
    }
  );

  router.get("(/_next/static/.*)", handleRequest); // Static content is clear
  router.get("/_next/webpack-hmr", handleRequest); // Webpack content is clear
  router.get("(.*)", async (ctx) => {
    const shop = ctx.query.shop;
    console.log('ACTIVE_SHOPIFY_SHOPS[shop] ', ACTIVE_SHOPIFY_SHOPS[shop], 'shop  ', shop);
    // This shop hasn't been seen yet, go through OAuth to create a session
    if (ACTIVE_SHOPIFY_SHOPS[shop] === undefined) {
      ctx.redirect(`/auth?shop=${shop}`);
    } else {
      await handleRequest(ctx);
    }
  });

  server.use(router.allowedMethods());
  server.use(router.routes());
  server.listen(port, () => {
    console.log(`> Ready on http://localhost:${port}`);
  });
});

On auth/callback also its giving 404 i.e

response: {
status: 404,
message: ‘Not Found’,
header: [Object: null prototype] { ‘set-cookie’: [Array] }
},