try {
    $opts = array(
        'http' => array(
            'user_agent' => 'PHPSoapClient'
        )
    );
    $context = stream_context_create($opts);
 
    $wsdlUrl = 'https://www.n11faturam.com/integrationservicewithoutmtom/IntegrationService.asmx?WSDL';
    $client = new SoapClient($wsdlUrl, array(
'ssl_method' => SOAP_SSL_METHOD_TLS,
'encoding'=>'UTF-8',
'cache_wsdl' => WSDL_CACHE_NONE,
'stream_context'=> stream_context_create(
array(
'ssl'=> array(
'crypto_method' => STREAM_CRYPTO_METHOD_TLSv1_2_CLIENT,
'ciphers' => 'SHA256',
'verify_peer'=>false,
'verify_peer_name'=>false,
'allow_self_signed' => true
)
)
)
)
     );
 
        $CorporateCode = 'xxx';
        $LoginName = 'xxx';
        $Password = 'xxx';
 
    $result = $client->GetFormsAuthenticationTicket($CorporateCode,$LoginName,$Password);
    print_r($result);
}
catch(Exception $e) {
    echo $e->getMessage();
}