The site was working fine and unexpectedly browsers started blocking the site confirming SSL fully not protecting. After a day, the site was completely down. Checking on the GCP instances and site, I was unable to find the actual issue.
Hence, I decided to create SNAPSHOT of the existing instance and create new instance. The configurations were complete, the multisite opened but the homepage (primary site) failed to. When tried to use IP address to enter the WP Deployment, the server could not respond. But, in mozilla browser it showed error message that the SSL is configured to my website not to the External IP address.
Therefore, I checked GCP to confirm External IP address. The instance details could not load Site Address and Admin URL. It shows a red circle with a white exclamation mark. Hovering on the exclamation mark displays message -->
"Failed to evaluate expression"
Please note that the newly created vm instance is not seen. The instance is the same old one that had problem.
How to solve this? Do I again need to create another instance from the Snapshot and configure? Where did I missed?