JetPack Connection Issue

Hello,
I have been facing the JetPack connection error on my website and I have tried almost everything to make it work from re-installing SSL, disabling themes/plugins to check any conflict, allowing all outbound connections to the host server and even added ModSecurity disable rule which allows /xmlrpc.php requests.
https://fullercarbon.com/xmlrpc.php is also working fine. And as per the SSL report from SSLLabs, the SSL is also installed and configured correctly.

However, the issue still remains there and that’s what I see in the JetPack dashboard:

“Outbound HTTPS not working
Your site could not connect to WordPress.com via HTTPS. This could be due to any number of reasons, including faulty SSL certificates, misconfigured or missing SSL libraries, or network issues.

Jetpack will re-test for HTTPS support once a day, but you can click here to try again immediately: Try again WordPress reports no SSL support

For more help, try our connection debugger or troubleshooting tips.”

I also double checked this with my host and they said even tried white-listing the IPs of JetPack and even had to disable blocking of any outbound request but it still didn’t work.

I’m looking for a detailed analysis so that we can point out the error.

Thank you!

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