webrequest sample code not working

[Satyam Shivam]

I am trying to run the sample code provide in the docs section of the mql5.com

https://docs.mql4.com/common/webrequest

I am trying to run the second code provided in the link above. 

I am not able to run this code . I am getting an error in the line where it tries to login at the given link.

   res=WebRequest("POST","https://www.mql5.com/en/auth_login",NULL,0,data,data,str);