Please help with REST API not work

Also, I have noticed that it is issue with latest version 5.8.7, I tried to rollback to previous versions, and it is working fine for me Please see the difference between V5.8.4 & V5.8.7 respectively.

I was facing this problem too using the API, so I add a form field with the name “_wpcf7_unit_tag” and the value “form_id”
Like this in react:
formData.append(“_wpcf7_unit_tag”, data.form_id);

Hope it help.

Am running a headless WordPress site, and have the same REST API submit problems listed above; have been unable to successfully send forms in the last month or so.

Last good version of CF7 for REST API form submittal: 5.8.5

Have followed the advice in this thread and spent many hours back and forth between the WordPress side & the form data on the front end to try to match the payload which works on the WordPress side.

This is the form submit from Vite dev server, which appears to match the payload from the WordPress embedded form page:

Payload:  FormData {
  [Symbol(state)]: [
    { name: 'your-email', value: '[email protected]' },
    { name: 'newsletter', value: 'SUBSCRIBE' },
    { name: '_wpcf7', value: '2039' },
    { name: '_wpcf7_version', value: '5.9.2' },
    { name: '_wpcf7_container_post', value: '3653' },
    { name: '_wpcf7_posted_data_hash', value: '' },
    { name: '_wpcf7_locale', value: 'en_US' },
    { name: '_wpcf7_unit_tag', value: 'wpcf7-f2039-p3653-o1' }
  ]
}
MLX Form Success:  {
  id: '1qyk770',
  valid: true,
  posted: true,
  errors: {},
  data: {
    email: '[email protected]',
    newsletter: 'on',
    _wpcf7_unit_tag: undefined,
    _wpcf7: undefined,
    _wpcf7_version: undefined,
    _wpcf7_locale: undefined,
    _wpcf7_container_post: undefined,
    response: 200
  },
  constraints: {
    email: { required: true },
    newsletter: { required: true },
    _wpcf7_unit_tag: { required: true },
    _wpcf7: { required: true },
    _wpcf7_version: { required: true },
    _wpcf7_locale: { required: true },
    _wpcf7_container_post: { required: true }
  }
}

The same payload to the same endpoint in Postman gives a unit tag error, although that is the unit tag from the WordPress version of the form page which works:

{"code":"wpcf7_unit_tag_not_found","message":"There is no valid unit tag.","data":{"status":400}}

It appears that in order to protect against SPAM, it is no longer possible to submit from React/Vue/SvelteKit frontend?

Any insight anyone has would be greatly appreciated. Would prefer not to stick at the older version, but it does still work.

All the best,
Morgan
🙏

• This reply was modified 2 years, 2 months ago by trulycool. Reason: form submitted before done writing

@nataliehoang91 glad you’ve got form submit working; still a no go for me 🙁

The only way I have found to get all the needed form data is:
– embed the shortcode in a Post or Page
– view the page (i.e. the WordPress version, not frontend rendered)
– right click on first form field and ‘inspect element’
– look for the <form> tag just above the first form field, and just below it there is a hidden <div> with all the CF7 ‘special fields’

<div style="display: none;">
    <input type="hidden" name="_wpcf7" value="2039">
    <input type="hidden" name="_wpcf7_version" value="5.8.5">
    <input type="hidden" name="_wpcf7_locale" value="en_US">
    <input type="hidden" name="_wpcf7_unit_tag" value="wpcf7-f2039-p3653-o1">
    <input type="hidden" name="_wpcf7_container_post" value="3653">
    <input type="hidden" name="_wpcf7_posted_data_hash" value="">
</div>

The first hidden <input) is _wpcf7, and that is the Form ID. The rest of the input are named in a self explanatory way.

All the best 🙏

Just noting that you can also get the wpcf7_unit_tag_not_found error if the unit tag is not being picked up because your API call is not formatted properly.

@trulycool it is worth testing it out in Postman first to isolate the problem and confirm it’s not your code. I eventually got mine working properly using Axios.

For those interested, you’ll need to add this to the request:

$request->set_param( '_wpcf7_unit_tag', <some_value> );

If you want to mimic what the plugin does, you can use this:

static $global_count = 0;
$global_count++;

$unit_tag = sprintf( 'wpcf7-f%1$d-o%2$d', $form_id, $global_count );
$request->set_param( '_wpcf7_unit_tag', $unit_tag );

where $form_id is the contact form post type ID.