{"error":{"code":899003,"message":"parameter invalid!"}} 老是返回这个错误，该有的参数都有了，不知道哪里还有问题

```
Jiguang.JMessage.JMessageClient client = new Jiguang.JMessage.JMessageClient(_appkey, _secret);
Dictionary<string, string> dic = new Dictionary<string, string>
{
{ "userType","1"}, { "chatId", ownUserid.ToString()}, { "merchantId",merchantid.ToString()}, { "merchantName",merchantName},
{ "imageUrl",""}, { "productName",""}, { "productId",productid.ToString()}, {"price","" }
};
TextMessage msg = new TextMessage();

            msg.TargetId = tuserid.ToString();
            msg.TargetType = "single";
            msg.FromId = fuserid.ToString();
            msg.TargetAppKey = _appkey;
            msg.TargetName = "2222222";
            msg.FromName = "111111";
            msg.IsNoNotification = true;
            TextMessage.MessageBody body = new TextMessage.MessageBody();
            body.Text = contents;

            body.Extras = dic;
            msg.Content = body;
            Jiguang.JMessage.Common.HttpResponse response = client.Message.Send(msg);
            string json = response.Content;