How to solve SOAP error "Error Fetching http headers"?

Question

PHP

Hello.
SOAP client config:

ini_set('default_socket_timeout', 5000);
//...
[
   'soap_version' => SOAP_1_2,
   'trace' => true,
   'keep_alive' => false, // или true - без разницы
   'connection_timeout' => 5000,
   'cache_wsdl' => WSDL_CACHE_NONE,
   'compression' => SOAP_COMPRESSION_ACCEPT | SOAP_COMPRESSION_GZIP | SOAP_COMPRESSION_DEFLATE,
]

When executing any method:

Error Fetching http headers

How to fix?
PHP 7.3. The SOAP service itself is written in C#.