Hello, I'm stuck about the en/de/nl process. Actually it is working in the main page but I can not fetch data, it is always fetching the locale first. Like: ContactForm.jsx:35
POST http://localhost:3000/tr/api/route 404 (Not Found)

My code:

const handleSubmit = async (e) => {
    e.preventDefault();
    try {
      const response = await fetch("/api/route", {
        method: "POST",
        headers: {
          "Content-Type": "application/json",
        },
        body: JSON.stringify(formData),
      });

      if (response.ok) {
        const data = await response.json();
        setSuccessMessage(data.message);
      } else {
        throw new Error("E-mail did not send. Please try again.");
      }
    } catch (error) {
      console.error(error);
      setErrorMessage(t("Contact16"));
    }
  };

Also:

import nodemailer from "nodemailer";

export default async function handler(req, res) {
  if (req.method === "POST") {
    console.log('Gelen veri:', req.body);
    try {
      const { name, email, company, phone, message, budget } = req.body;

      const transporter = nodemailer.createTransport({
        host: "smtp-mail.outlook.com",
        secureConnection: false,
        port: 587,
        tls: {
            ciphers: 'SSLv3'
        },
        auth: {
          user: process.env.MAIL_USER,
          pass: process.env.MAIL_PASS,
        },
      });

      const mailOptions = {
        from: process.env.MAIL_USER,
        to: process.env.MAIL_TO,
        subject: "New Job Request",
        text: `
          Name: ${name}
          Email: ${email}
          Company: ${company}
          Phone: ${phone}
          Message: ${message}
          Budget: ${budget}
        `,
      };

      await transporter.sendMail(mailOptions);

      res.status(200).json({ success: true, message: "E-mail sent!" });
    } catch (error) {
      console.error(error);
      res
        .status(500)
        .json({
          success: false,
          message: error.message,
        });
    }
  } else {
    res.status(405).end();
  }
}

It is fetching the wrong locale and I did not fix. Also it contains the different error like pathname. So I'm trying to fix all of them.
Also my middleware:

import createMiddleware from "next-intl/middleware";
import { pathnames, locales, localePrefix } from "./config";

export default createMiddleware({
  defaultLocale: "en",
  locales,
  pathnames,
  localePrefix,
});



export const config = {
  matcher: [
    // Enable a redirect to a matching locale at the root
    "/",
    

    // Set a cookie to remember the previous locale for
    // all requests that have a locale prefix
    "/(tr|de|en)/:path*",

    // Enable redirects that add missing locales
    // (e.g. `/pathnames` -> `/en/pathnames`)
    "/((?!_next|_vercel|.*\\..*).*)",
  ],
};

i18n file

import { notFound } from "next/navigation";
import { getRequestConfig } from "next-intl/server";
import { locales } from "./config";

export default getRequestConfig(async ({ locale }) => {
  // Validate that the incoming `locale` parameter is valid
  if (!locales.includes(locale)) notFound();

  return {
    messages: (
      await (locale === "en"
        ? // When using Turbopack, this will enable HMR for `en`
          import("./messages/en.json")
        : import(`./messages/${locale}.json`))
    ).default,
    timeZone: "UTC",
  };
});

config

export const locales = ["en", "tr", "de"];

export const pathnames = {
  "/": "/",
};

// Use the default: `always`
export const localePrefix = undefined;

Thanks for helping...