Let's Encrypt certificate is not installed with the fallowing error:
PLESK_ERROR: The authorization token is not available at http://example.com/page1/WZHzw8e9HGAqMz-Kvu76RvNc9OiqiXZ-ee1AjTGrjkM. The token file 'D:\domains\example.com\httpdocs\\page1\WZHzw8e9HGAqMz-Kvu76RvNc9OiqiXZ-ee1AjTGrjkM' is either unreadable or does not have the read permission. To resolve the issue, correct the permissions on the token file to make it is possible to download it via the above URL.
In Plesk > Domains > example.com > Hosting Settings, domain is assigned to one IP address, but globally it is resolved to the other IP address.
Incorrect DNS settings on domain registrar's side.
Contact your name registrar Set up DNS settings to match the IP address that is assigned in Plesk to the global one.