Google Cloud App Engine冲突错误：应用已存在却无法查询

我的项目出现了矛盾的状态提示：系统既说项目里存在App Engine应用，又说不存在。

已完成的排查操作 #

• 尝试通过UI用默认配置创建应用，收到*"Error while initializing App Engine"*错误提示。
• 验证过项目配置信息。
• 尝试部署一个无额外配置的hello-world Node.js应用（app.yaml未做额外设置）。
• 排查过区域不匹配问题。

命令执行输出 #

$> gcloud app create --project=xxxx-000000 --region=us-central

You are creating an app for project [xxxx-000000].
WARNING: Creating an App Engine application for a project is irreversible and the region
cannot be changed. More information about regions is at
https://cloud.google.com/appengine/docs/locations.
ERROR: (gcloud.app.create) The project [xxxx-000000] already contains an App Engine application. You can deploy your application using 'gcloud app deploy'.

$> gcloud app describe

ERROR: (gcloud.app.describe) The current Google Cloud project [xxxx-000000] does not contain an App Engine application. Use 'gcloud app create' to initialize an App Engine application within the project

内容的提问来源于stack exchange，提问作者Brend