Soap Curl request error - 400 Bad Request - php

Question

I am making soap curl request and here is the code:
$headers = array(
"Content-type: text/xml;charset=\"utf-8\"",
"Accept: text/xml",
"Cache-Control: no-cache",
"Pragma: no-cache",
"SOAPAction: \"http://tempuri.org/Save_ExMsgInfo2\"",
"Content-length: ".strlen($xml_post_string),
);
$ch= curl_init();
curl_setopt($ch, CURLOPT_URL, "https://xxx.yyy.com:517/zzz.asmx" );
curl_setopt($ch, CURLOPT_RETURNTRANSFER, false);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
curl_setopt($ch, CURLOPT_POST, true );
curl_setopt($ch, CURLOPT_POSTFIELDS, $xml_post_string); // the SOAP request
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
curl_setopt($ch, CURLOPT_USERAGENT,'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.17 (KHTML, like Gecko) Chrome/24.0.1312.52 Safari/537.17');
curl_setopt($ch, CURLOPT_HEADER, 1);
curl_setopt($ch, CURLINFO_HEADER_OUT, true);
if(curl_exec($ch) === false)
{
$err = 'Curl error: ' . curl_error($ch);
curl_close($soap_do);
return $err;
}
else
{
curl_close($ch);
return 'Operation completed without any errors';
}
But getting below error
HTTP/1.1 400 Bad Request
Cache-Control: private
Server: Microsoft-IIS/7.5
X-AspNet-Version: 2.0.50727
X-Powered-By: ASP.NET
Date: Wed, 01 Jul 2020 16:42:35 GMT
Content-Length: 0
Any soln?