Let's Encrypt - errot Failed to get registration by key

1

starting version 3.2.4
Saving debug log to /var/log/letsencrypt/letsencrypt.log
Plugins selected: Authenticator standalone, Installer None
Obtaining a new certificate
An unexpected error occurred:
The server experienced an internal error :: Failed to get registration by key
Please see the logfiles in /var/log/letsencrypt for more details.

How to solve this error?

2

Can someone explain how to use Let’s Encrypt from hassio addons?