HTTPWebRequest.GetResponce for NTLM protocol not working on Android

I am trying to access data from IIS Server protected by NTLM protocol using HTTPWebRequest, which works fine on unity editor( windows ) but fails in Android Mobile App.

I am getting 401 Unauthorized Access error, but works fine in editor and getting the expected response.

Please help me,

Please let me know, if there is any alternative through which i can access the server which is protected(NTLM protocol, I need to provide the authentication)

Server shall be accessed successfully every time through browser, both in Desktop and in Mobiles.