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I have checked the cURL not working properly
When I run the command curl -I https://www.example.com/sitemap.xml
curl: (7) Failed to connect
Failed to connect on all port
this error only on one domain, all other domain working fine, curl: (7) Failed to connect to port 80, and 443
Thanks...
After many search, I found that Hosts settings not correct
Then I check nano /etc/hosts
The Domain point to wrong IP in hosts file
I change the wrong IP and its working Fine
This is new error Related to curl: (7) Failed to connect