问找不到feign client的kotlin.Unit类型的回退实例

EN

Unsatisfied dependency expressed through constructor parameter 0; 
nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'com.claro.mcp.client.McpUaaClient'
: FactoryBean threw exception on object creation; 
nested exception is java.lang.IllegalStateException: No fallback instance of type class kotlin.Unit found for feign client mcpuaa

Error creating bean with name 'com.claro.mcp.client.McpUaaClient': FactoryBean threw exception on object creation; nested exception is java.lang.IllegalStateException: No fallback instance of type class kotlin.Unit found for feign client mcpuaa

@AuthorizedFeignClient(name = "mcpuaa")
public interface McpUaaClient {
    @PostMapping("/api/auth/validatePassword")
    ResponseEntity<JsonObject> validatePassword(String password);
}