If you are getting below error in Plesk while installing SSL then then you can check this article further.
You are getting this error it means TXT record is missing from your account or its incorrect. you can check below steps:
Error: Could not issue a Let's Encrypt SSL/TLS certificate for example.com Authorization for the domain failed. Details Invalid response from https://acme-v02.api.letsencrypt.org/acme/authz/9_fD4pJYnd6o4DNUxbG0WNtYOOm-G6TeHcz8TN1K9f4. Details: Type: urn:ietf:params:acme:error:unauthorized Status: 403 Detail: Incorrect TXT record "Rq5AN5tnNTHnUNfh2byBWzDZNePjIOcSJDMJYK0ku6A" found at _acme-challenge.example.com
- Login to Plesk.
- Here you will find option “Let’s Encrypt” under “Websites and Domains”.
- Now you will find various options and you have check “Issue a wildcard SSL/TLS certificate” option.
- At the end you will find option “Install”, you have to click on it.
- Further you will find TXT record and you have to add the TXT record in DNS service option.
- After that click on “Continue” button.