Laravel 5.5执行SOAP调用

I don't have a lot of experience with SOAP but I need to do a SOAP call from my Laravel application to fetch an object. I have an example in my SOAP UI so basically I need to find a way to do the exact same thing in my code.

Unfortunately I am a bit blocked and I get no clear error message so honestly I have no idea what is going wrong. Probably a lot :D

error message:

SoapFault

No message

What I have tried:

$soapClient = new \SoapClient(__DIR__ . '/SoapMCS.wsdl');

$headerbody = [
    'X-MCS-Auth-Username' => 'username',
    'X-MCS-Auth-Password' => 'password'
];

$header = new \SoapHeader(__DIR__ . '/SoapMCS.wsdl', 'credentials', $headerbody);
$soapClient->__setSoapHeaders($header);

$test = 'hello';
$result = $soapClient->getMaintenanceObject($test);

dd($result);