html.AntiForgeryToken not working on Nginx?

Question

EDIT:__RequestVerificationToken can not found when using nginx, why?

Rhis is my validation code, it always returns an error when using nginx, if I do not use nginx, it is OK. We are using nginx because we have many machines to point at the same host. Rhanks.

public class MyValidateAntiForgeryToken : AuthorizeAttribute
{
    public override void OnAuthorization(AuthorizationContext filterContext)
    {
        var request = filterContext.HttpContext.Request;
        if (request.HttpMethod== WebRequestMethods.Http.Post)
        {
            if (request.IsAjaxRequest())
            {
                var antiForgeryCookie = request.Cookies[AntiForgeryConfig.CookieName];
                var cookieValue = antiForgeryCookie != null
                    ? antiForgeryCookie.Value : null;
                AntiForgery.Validate(cookieValue, request.Headers["__RequestVerificationToken"]);
            }
            else
            {
                new ValidateAntiForgeryTokenAttribute()
  .OnAuthorization(filterContext);
            }
        }
    }

this is my front code:

 var token = $('@Html.AntiForgeryToken()').val();
                        var headers = {};
                        headers["__RequestVerificationToken"] = token;

                        $.ajax({
                            type: 'POST',
                            url: '@Url.Action("BuyProduct", "PpdaiVip")',
                            cache: false,
                            headers: headers,
                            data: arr,
                            success: function (e) {
                                if (e.IsSuccess) {
                                }
                    });