Getting "you must provide a model parameter" for Whisper

API
1

No matter what, i get “you must provide a model parameter”. Here is my PHP code:

        $ch = curl_init();
        $headers = [ 
            'Authorization: Bearer ' . $model['api_key']
        ];
        $post_data = [
            'file' => new CURLFile($audio['tmp_name']),
            'model' => 'whisper-1'
        ];
        curl_setopt($ch, CURLOPT_POSTFIELDS, $post_data);
        curl_setopt($ch, CURLOPT_URL, $model['endpoint']);
        curl_setopt($ch, CURLOPT_POST, true);
        curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($ch, CURLOPT_TIMEOUT, 30);

        $response = curl_exec($ch);

$response is always:
“error”: {
“message”: “you must provide a model parameter”,
“type”: “invalid_request_error”,
“param”: null,
“code”: null
}

I tried everything, including following the manual to the tee… This is crazy! Any ideas?