为什么我的nacos，用resttemplate调接口，解析不了服务名？

为什么我的nacos，用resttemplate调接口，解析不了服务名？
严重: Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed: org.springframework.web.client.ResourceAccessException: I/O error on GET request for "http://email-service/c/callProvider": email-service] with root cause
java.net.UnknownHostException: email-service
at java.base/sun.nio.ch.NioSocketImpl.connect(NioSocketImpl.java:572)
at java.base/java.net.Socket.connect(Socket.java:633)