Data at the root level is invalid php SoapClient - php

Question

I have to create a SOAP header like:
<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
<soap:Header>
<AuthHeader xmlns="URL">
<Username>string</Username>
<Password>string</Password>
<PublicKey>string</PublicKey>
<NewPassword>string</NewPassword>
<UserType>string</UserType>
</AuthHeader>
</soap:Header>
<soap:Body>
<getClients xmlns="URL" />
</soap:Body>
</soap:Envelope>
Connect with WS With sesion(), it returns nothing, but when the XML contains something, I get that error.
This is my code:
$wsdl= "URL?wsdl';
$options = array(
'uri'=>'http://schemas.xmlsoap.org/soap/envelope/',
'style'=>SOAP_RPC,
'use'=>SOAP_ENCODED,
'soap_version'=>SOAP_1_1,
'cache_wsdl'=>WSDL_CACHE_NONE,
'connection_timeout'=>15,
'trace'=>true,
'encoding'=>'UTF-8',
'exceptions'=>true,
);
try {
$soap = new SoapClient($wsdl, $options);
$valor = $soap->getPublicKey();
}
catch(Exception $e) {
die($e->getMessage());
}
$key=$valor->getPublicKeyResult->any;
$endpoint = 'url';
$user;
$password;
$password64 = mb_convert_encoding($password,'UCS-2LE','auto');
$rsa = new Crypt_RSA();
$rsa->setEncryptionMode(CRYPT_RSA_ENCRYPTION_PKCS1);
$rsa->loadKey($key);
$rsa->setPublicKey($key);
$ciphertext = $rsa->encrypt($password64);
$cipher64 = base64_encode($ciphertext);
$headerbody = array(
'PublicKey'=>$rsa->getPublicKey(),
'Username'=>$user,
'Password'=>$cipher64,
'NewPassword'=>'',
'UserType'=>'U'
);
$header = new SOAPHeader($endpoint, 'AuthHeader', $headerbody);
$soap->__setSoapHeaders($header);
try {
$data = $soap->sesion();
$data = $soap->getClients();
}
catch(Exception $e) {
die($e->getMessage());
}
var_dump($soap->__getTypes());
echo "REQUEST:\n" . htmlentities($soap->__getLastRequest()) . "\n";
echo "RESPONSE:\n" . htmlentities($soap->__getLastResponse()) . "\n";
var_dump($data);
die;
And the header that form:
<?xml version="1.0" encoding="UTF-8"?>
<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" xmlns:ns1="URL">
<SOAP-ENV:Header>
<ns1:AuthHeader>
<ns1:Username>$user</ns1:Username>
<ns1:Password>$password</ns1:Password>
<ns1:PublicKey>-----BEGIN PUBLIC KEY-----
 PUBLIC KEY#13; -----END PUBLIC KEY-----</ns1:PublicKey>
<ns1:NewPassword></ns1:NewPassword>
<ns1:UserType>U</ns1:UserType>
</ns1:AuthHeader>
</SOAP-ENV:Header>
<SOAP-ENV:Body>
<ns1:getClients/>
</SOAP-ENV:Body>
</SOAP-ENV:Envelope>
I have tried various solutions proposed and none of them work, I'm not able to include in the envelope the xlms:xsi, xlms:xsd. And I think that is what I need.