Okey so, first, thank you all for your help. It all seems to be working well, but I have an issue, when I change the header to "application/json", it looks like it is not changing the header, but adding it to it, so when I look in my server, the Content type i'm sending is: application/x-www-form-urlencoded, application/json, and it ruins all, is any way to remove this application/x-www-form-urlencoded?