in laravel soap give me wrong version error once in a while?

I try to use soap and connect to wsdl file. I don't know why 2 from 10 request send but other give me wrong version error. I defined version in call soap by

'soap_version'=>        SOAP_1_1,

wsdl start with this :

<?xml version="1.0" encoding="utf-8"?>
<wsdl:definitions xmlns:tm="http://ift.tt/L9w5lv" xmlns:soapenc="http://ift.tt/wEYywg" xmlns:mime="http://ift.tt/L9w8xG" xmlns:tns="http://tempuri.org/" xmlns:soap="http://ift.tt/KIQHA2" xmlns:s="http://ift.tt/tphNwY" xmlns:soap12="http://ift.tt/1fBjFB5" xmlns:http="http://ift.tt/1fBjHsH" targetNamespace="http://tempuri.org/" xmlns:wsdl="http://ift.tt/LcBaVt">

error show me like this :

 "message": "Wrong Version",
  "status_code": 500,

via Chebli Mohamed