SignInManager.GetExternalLoginInfoAsync() returns null

I'm using WeChat authentication a third party clients which written by myself. I'm getting null when the application returns to my ExternalLoginCallback action and asks the SignInManager for the login info. I've registered a callback in the twitter middleware for when the ticket is being created and I've confirmed that I've received the  access token and user information from WeChat. 

This is a new application templated by VS 2015 update 3. 

cookies looks like this:

startup.cs

app.UseWeChatAuthentication(new WeChatOptions() { AppId = "***", AppSecret = "***" });

WeChatOptions:

AuthenticationScheme = WeChatDefaults.AuthenticationScheme;
DisplayName = AuthenticationScheme;
CallbackPath = new PathString("/signin-wechat");
RedirectUri = "/Account/ExternalLoginCallback";
AuthorizationEndpoint = WeChatDefaults.AuthorizationEndpoint;
TokenEndpoint = WeChatDefaults.TokenEndpoint;
UserInformationEndpoint = WeChatDefaults.UserInformationEndpoint;

thx for help