Ошибка Curl 422 при использовании переменных в Postfields и заголовке

Question

Мой запрос Curl генерируется почтальоном. Я только что изменил исходные значения на переменные из заголовков curl, но когда я использую переменные, я получаю код состояния 422, но когда я помещаю код напрямую, у него нет проблем

Значение переменныхдолжно быть: но я не определил их в моем php-файле, в моем html-файле есть текстовое поле с $ _POST

$auth = POST /c4/v1/login HTTP/1.1
Authorization: 
X-UDID: vQsWMNO6Cta92exe82IArHBjgpbCbDHT
X-Signature: QLZLZ+pfki0W7hhb5ZPRJzJzJG5x3n1AgYrxtbLP3A7iHrkDwYx8Ei5vFW5KTnsRaJ5qWVRu9QMI7uvEO6SoD/MVwiM9NpZHlN1seocSheG9F7nwL/NFe4btxaurVV9/8yoftg26PyydviKIpCmog8zQvS01Oi/EgUGMRAWc8DX5uwbS89Q0dqL4yZ7GfdwI4sUYA9hOVB8DZ064k6nXttNZNo/NpFYzwAmNOpp078wCcuuLEWPCW59SJRCOCn+fbOsMtwIvLUigAk+lKoyidPzilqCZ8Fn1jF9cRUm6Kbrp6/I8RYHDYh7IO/J2JmFEISj2stxHIhSOIz//qLdplw==
X-FlowId: 0a880a5d-12e4-467f-be3e-2b6e48772286
X-Env-Info: eyJhcHBWZXJzaW9uIjoiNS4yMS4yOjQ3NSIsImNoYW5uZWwiOiJHQ0FTSF9BUFAiLCJleHRlbmRJbmZvIjp7Imxic0Vycm9yQ29kZSI6IjEwMDMifSwib3JkZXJUZXJtaW5hbFR5cGUiOiJBUFAiLCJvc1R5cGUiOiJBbmRyb2lkIiwib3NWZXJzaW9uIjoiNS4xLjEiLCJ0ZXJtaW5hbFR5cGUiOiJBUFAiLCJ0b2tlbklkIjoiM2xpRmkxL3hDcmJ5eE91RUdwMFpvL1Z5UWorWE5zaGlEWWQ2ZG93anhRNE43WTdvYlFFQUFBXHUwMDNkXHUwMDNkIiwiVXNlci1BZ2VudCI6IkdDYXNoIEFwcCBBbmRyb2lkIiwiWC1ERlAtVE9LRU4iOiIzbGlGaTEveENyYnl4T3VFR3AwWm8vVnlRaitYTnNoaURZZDZkb3dqeFE0TjdZN29iUUVBQUFcdTAwM2RcdTAwM2QiLCJYLUFQUC1WRVJTSU9OIjoiNS4yMS4yOjQ3NSIsIlgtUEhPTkUtQlJBTkQiOiJnb29nbGUiLCJYLVBIT05FLU1BTlVGQUNUVVJFUiI6Imdvb2dsZSIsIlgtUEhPTkUtTU9ERUwiOiJnb29nbGUgUGl4ZWwgMiIsIlgtUEhPTkUtT1MtVkVSU0lPTiI6IjUuMS4xLDIyIiwiWC1VRElEIjoidlFzV01OTzZDdGE5MmV4ZTgySUFySEJqZ3BiQ2JESFQifQ==
X-Package-Id: eyJwYWNrYWdlSWQiOiJIRkl5bmd4enpKVHJpZVlmL2dhVEt5QnlKaVVFVUM3RlNMWnVNUHFOSURyeHFDVStsWW1halJsZ2RDOFVvK3RLSjc0eHc5MFkxQXpuRTdjUGhxOVB5dVQ5b0FwL0JpSC9XS2QwbllsQm8xOWtXRkdtdlp2dnlIN24ybkZDUHRrR0xlQTZ2b2FKb0J0dTRvWjFab211VzBnejJGQUxQQXhmV05DSzE1bXNyRmF2SWk4VEZwYUtOd2IxcVdpR0VMVHJPcEJSbUx4bzNPcFpLOHVrNHBYajIzK08rL0ZOeUJQQ0Q3N2RWeVRnblozOFBkbU1GaDFTemlGOE5XMHpvQnI5UkZDUkVBdjBoeXFJMTAxTEpodTNCdFpYeWd0WnZXdjdUTVBvekZhY2NKS0d3cFVNU2dBdjFKc0x0N3lmaFhhdWVFUkFPM05jN29pbHJrdDZBcHpnRVE9PSIsImVuYyI6WyJwYWNrYWdlSWQiXX0=
X-Package-Signature: p1F3byHrwA//i3X22RLm2T+8eXnZOsnxRiHBL8H4T3/uHbSE50nCX5RB2Lbv489lOoY8a3PgDzZlrOjK1KcoA6fQrCrxjJuwvcBf1ebFOL8BGfhaSoYfOemtYUrhukxLSSpfqfhBqF7wBewmU7qLtnC7hX17qCkqyv+xKg7JwP5Klw12wAX4tK4H5EtyoZG+Vnmi+xuzpfsEot2SDd5fPG/4gR3LJFmXho/foCZDKKauEQ0KB3jrk7uj2u6oe8hgpUIX2cquRnS/s02B0AT1mM3T70Nb9F6MyNNLnXzpSyH1qq8SVwB1dMtcceLmskFVKrOL0wYxCsQWJp42OEabIA==
X-Correlator-Id: 
X-Service-Prefix: -ap
Content-Type: application/json
Content-Length: 2669
Host: api.mynt.xyz
Connection: Keep-Alive
Accept-Encoding: gzip
User-Agent: okhttp/3.12.0

$mpin = {"mpin":"VBdieZKm37Ep9DYgr+n5KC8NsJQ9XGD0/YNgacT2pXntXUeVlv6sc3Yy3LNlwZoYQglRWArdPcLzSl9FR+JU3B4prXUT3TM4qWAxbPUfxqAcGrBAsyeuSw/Sur8ncWae8AhxnBTLWFHL4pvBS6e9uHvJ+11j06ZU4CiMmnS/DzpRzJSzu5Ws1vAj/ACmRXQTx0A8kruBtGBMt2aZsHTjKmqrWFXS2nptlpDgffahnFJpKV2k/oMb3mXJv9BLGsoRelHCuvA07FT1O8KQkP1j9Cj+UgtdD6oJ91DuAJnCPbFLbsGHdeO3BVqfYoQ67buih6UluvJ/O2EQO8hbe7vIBQ==","rds_data":"{\"version\":\"2\",\"data\":\"0b996fe64d7e7666776c757113ce5b8581a6435447b982a79816ef11ebd06b3187b2bb879127493e7f2df20f4556f651022e2aeb834640a21f7679a9bc3d9dce68a5f0a9658aa78e726194146497d1497ad3c75f1c59b46e9e0785f3921f95eeb3d62666734b20677c8a5dbaf5dd81e3ac7b83c6260f87a784b4470"}","enc":["mpin"]}

Мой код:

<?php
error_reporting(0);

$auth = $_POST['auth'];
$mpin = $_POST['mpin'];
$auth = str_replace(" ", '', "$auth");
$auth = preg_replace('/(?<=.)\s\n?/', '",<br> "', $auth);
$auth = str_replace(':', ': ', "$auth");
$mpin = addslashes($mpin);
$auth = preg_split("/[\s]+/", "$auth");
   unset($auth[0]);
   unset($auth[1]);
    unset($auth[2]);
    unset($auth[3]);
   unset($auth[16]);
    unset($auth[17]);
   $auth = implode(" ",$auth);
if(empty($auth)){

    echo 'The auth token is empty.  Please enter right auth token numbers';
    exit;

    //Code to be executed if the statement is true 
}

$curl = curl_init();

curl_setopt_array($curl, array(
  CURLOPT_URL => "https://api.mynt.xyz/c4/v1/login",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 100,
  CURLOPT_TIMEOUT => 300,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => "$mpin",
  CURLOPT_HTTPHEADER => array(
    "Accept: */*",
    "$auth",
  ),
));
$response = curl_exec($curl);


$responseauth = str_replace("{\"access_token\":\"","",$response);
$responseauth = str_replace("\"}","",$responseauth);
?>
<html>
<b>Login successfull! <br> <br></b> 
<fieldset enabled><legend>Temporary Auth Token</legend>
<p>Temporary auth token: <?php echo $responseauth; ?> </p>
<form name='form' method='post' action="balance/index.php">
<p>Please enter your temporary auth token:  <input type="text" name="authtoken" id="authtoken"  <br/>
<input type="submit" name="submit" value="Submit">  


</html>