您没有付费的开发者帐户，对吗?

You don't have a paid developer account, do you?

如果您拥有免费的开发者帐户，则证书仅有效七天.这就是为什么您必须每7天在设备上重新安装应用程序的原因.

If you have the free developer account, the certificate will stay valid only seven days. That's why you have to reinstall you apps every 7 days on your devices.