diff --git a/notes/helloshop/ordering-service.md b/notes/helloshop/ordering-service.md
index 782cb7f..1b34b4c 100644
--- a/notes/helloshop/ordering-service.md
+++ b/notes/helloshop/ordering-service.md
@@ -69,8 +69,7 @@ builder.Services.AddMediatR(options => options.RegisterServicesFromAssembly(Asse
 ```
 
 ## 使用 Mediator 请求管道处理 CQRS 中的命令
-
-![ordering-service-identified-command](https://oss.xcode.me/notes/helloshop/ordering-service-identified-command.svg)
+=
 
 `LoggingBehavior`、`ValidatorBehavior` 和 `TransactionBehavior`
 
@@ -92,6 +91,12 @@ builder.Services.AddScoped(typeof(IPipelineBehavior<,>), typeof(ValidatorBehavio
 builder.Services.AddScoped(typeof(IPipelineBehavior<,>), typeof(TransactionBehavior<,>));
 ```
 
+## 消息去重机制
+
+
+![ordering-service-identified-command](https://oss.xcode.me/notes/helloshop/ordering-service-identified-command.svg)
+
+
 ## 实现 CQRS 中的 Query 模式
 
 ```csharp