请教宝塔安装Let's Encrypt证书出错。

申请Let's Encrypt的SSL证书出现如下错误：

证书获取失败，返回如下错误信息：

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Certificate not yet due for renewal; no action taken.
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Saving debug log to /var/log/letsencrypt/letsencrypt.log
Plugins selected: Authenticator webroot, Installer None
Cert not yet due for renewal
Keeping the existing certificate