I’m trying to submit a form using Next.js, Resend, React Email. The browser gives ‘500 Internal Server Error’ and the reason is that ‘TypeError: req.json is not a function’. How to solve it? Is there any ideas?

  async function onSubmit(values: FormInput) { 
    await fetch('/api/send/', {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
      },
        body: JSON.stringify({
        fullname:values.fullname,
        email:values.email,
        phone:values.phone,
        message:values.message,
        }),
    }).then(() => {
      console.log('Application Submitted');
    });
    reset();
  }  

And in send.ts file I write this code

import { Resend } from 'resend';
import { NextRequest, NextResponse } from 'next/server';
import EmailCompany from '@/components/job-container/EmailCompany';

const resend = new Resend('re_Pu73K6n2_CktZzeybNrLrf6EA65sqHXmD');

async function POST(req: NextRequest) {
  const { name, email, phone, message, file, attachments } = await req.json();

  try {
    const data = await resend.emails.send({
      from: '[email protected]',
      to: email,
      subject: `Application for Open Positions`,
      react: EmailCompany({ name, email, phone, message, file }),
    });

    return NextResponse.json(data);
  } catch (error) {
    return NextResponse.json({ error });
  }
}

export default POST;

When I am trying print ‘console.log({ req: req.body })’, it returns me empty object.Why does this happen and how to fix it?