Returns 400 Bad Request for POST Request Method.

Just post one more parameter named _wpcf7_unit_tag with any non-empty value.

Thanks Madex, your solution worked.

Hello,

just faced the same problem, solution also worked, but I can’t find the information what is the purpose of this unit tag?

Hello, thank you for the solution.

Adding ‘_wpcf7_unit_tag’ to the POST request solves the issue.

This tag was implemented in February’s update — https://contactform7.com/2024/02/05/contact-form-7-587/.

When I asked ChatGPT for help I got this answer:

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The _wpcf7_unit_tag is a hidden field that Contact Form 7 uses for internal tracking. When you submit a form, Contact Form 7 expects this field to be included in the POST request. The value of this field is usually a string that starts with wpcf7-f followed by the form ID and a dash - and then a random number.

If you’re making a POST request manually (like in your Next.js code), you’ll need to include this field in your formData object. The value can be any non-empty string, but it’s a good practice to follow the format that Contact Form 7 uses.

Here’s how you can modify your formData object to include the _wpcf7_unit_tag field:

let formData = {
  // your other form fields here...
  _wpcf7_unit_tag: 'wpcf7-f' + formId + '-123'
};

In this example, replace formId with the actual ID of your form and 123 with any random number. Then, you can use this formData object in your fetch request.

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