consumer 服务覆盖

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## Ask your question here
我有两个consumer A和consumer B 注册到nacos时，只发现一个consumer B 的服务，具体是以谁最后注册到nacos为准，请问这是为啥

Start by identifying how the two consumers register with Nacos and how the service list is represented there. Compare the registration and discovery configuration for consumers A and B, then confirm whether both instances appear and determine which registration behavior is expected.

Written by the indexing model from the issue text.