Add the message

<?php
include('nusoap/nusoap.php');

$client = new soapclient('https://www.mdworks.info/_soap/control.php');
$params = [
    'id_campagne' => 12345,
    'login'       => 'your_login',
    'motdepasse'  => 'your_password',
    'url'         => 'https://your-domain.com/message.html',
];

$ok = $client->call('Modif_Message_Campagne', $params);

if ($client->fault) {
    die("SOAP error: {$client->faultstring}");
}

echo $ok;

<?php
try {
    $client = new SoapClient(null, [
        'location' => 'https://www.mdworks.info/_soap/control.php',
        'uri'      => 'https://www.mdworks.info',
        'encoding' => 'ISO-8859-1',
    ]);

    $ok = $client->Modif_Message_Campagne(
        12345,
        'your_login',
        'your_password',
        'https://your-domain.com/message.html'
    );

    var_dump($ok);
} catch (SoapFault $fault) {
    trigger_error("SOAP Fault: ({$fault->faultcode}) {$fault->faultstring}", E_USER_ERROR);
}

curl -X POST https://www.mdworks.info/_soap/control.php \
  -H 'Content-Type: text/xml; charset=utf-8' \
  -H 'SOAPAction: ""' \
  -d '<?xml version="1.0" encoding="UTF-8"?>
<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/">
  <SOAP-ENV:Body>
    <Modif_Message_Campagne>
      <id_campagne>12345</id_campagne>
      <login>your_login</login>
      <motdepasse>your_password</motdepasse>
      <url>https://your-domain.com/message.html</url>
    </Modif_Message_Campagne>
  </SOAP-ENV:Body>
</SOAP-ENV:Envelope>'

from zeep import Client

client = Client('http://www.mdworks.info/_soap/control.php?wsdl')
ok = client.service.Modif_Message_Campagne(
    id_campagne=12345,
    login='your_login',
    motdepasse='your_password',
    url='https://your-domain.com/message.html',
)

print(ok)

import axios from 'axios';

const envelope = `<?xml version="1.0" encoding="UTF-8"?>
<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/">
  <SOAP-ENV:Body>
    <Modif_Message_Campagne>
      <id_campagne>12345</id_campagne>
      <login>your_login</login>
      <motdepasse>your_password</motdepasse>
      <url>https://your-domain.com/message.html</url>
    </Modif_Message_Campagne>
  </SOAP-ENV:Body>
</SOAP-ENV:Envelope>`;

const { data } = await axios.post(
  'https://www.mdworks.info/_soap/control.php',
  envelope,
  { headers: { 'Content-Type': 'text/xml; charset=utf-8' } },
);
console.log(data);