Welcome Nagendra Vara Prasad Chellu,
Thank you for sharing the information. Based on your description, this appears to be related to certificate validation and verification through the issuing organization's website or QR code system, rather than a Windows-related issue.
Since the verification process is managed by the certificate issuer, I recommend contacting the organization that issued the certificate or using their official verification portal for further assistance.
As this is outside the scope of Windows support, I may not be able to provide additional troubleshooting for the certificate verification process. Thank you for your understanding.