Urgent: Resolve 404 Not Found on HTTPS/LiteSpeed Server

We are urgently seeking an experienced freelancer to troubleshoot and fix a technical issue with our website hosted on a LiteSpeed server running Ubuntu.

Current Situation/Problem:

We have successfully installed an SSL certificate (HTTPS) on the domain.

The server environment is LiteSpeed on Ubuntu.

After the SSL setup, when accessing the website via HTTPS, the browser returns a "404 Not Found" error (The message displayed is: "The resource requested could not be found on this server!").

The site works correctly via HTTP (before redirection), but fails with 404 when accessing HTTPS.

Simple Task:

Your sole task is to diagnose the root cause and fully resolve the 404 error, ensuring the website loads correctly and securely over HTTPS.

Technical Requirements (Must have experience with):

LiteSpeed and/or OpenLiteSpeed server configuration.

Ubuntu Server environment.

Configuring SSL/TLS and Chain Certificates (CA Bundle).

Troubleshooting and configuring .htaccess files or Virtual Host settings on LiteSpeed.

Diagnosing 404 errors related to server or SSL configuration.

Access:

We will provide necessary access (SSH, Hosting Control Panel, etc.) upon agreement.