You can check your curl again:curl -Iv https://yourdomain.comResults:SSL connection using TLS1.2 ...* Server certificate:* subject: CN=yourdomain.com* issuer: <Tên Intermediate CA>If results:curl failed to verify the legitimacy of the serverHow to fix:You install SSLCertificateChainFile. For your host.Reason:Server not send Intermediate CAFacebook bot, curl, Zalo, OpenGraph tester was wrong SSL:Was Not get OG title/description/imagePreview not shownBot failure notify 400/SSL handshake error