Cert Verifier- Verification Error

Hello, I am using cert-issuer since past few days so I was able to issue the certificate on testnet bitcoin using sample unsigned certificates available at this path “examples/data-testnet/unsigned_certificates” I am doing this by REST so it gives me some output when I take that output and try to pass it in cert verifier for the verification I got this output
ERROR:root: Verification step VerificationGroup failed!
ERROR:root: Verification step VerificationGroup failed!
Checking certificate has not been tampered with, failed
Checking certificate has not expired,not_started
Checking not revoked by issuer,not_started
Checking authenticity,not_started
Validation,failed

But if I pass the sample signed certificate located here /cert-verifier/tests/data/2.0/testnet.json it worked well see the below output

Checking certificate has not been tampered with,passed
Checking certificate has not expired,passed
Checking not revoked by issuer,passed
Validation,mock_passed

So I am not sure what I am doing wrong, the first thing which came in mind after doing some research is I am using an unsigned certificate which has a different public key and I am signing them from my testnet wallet address so cert verifier is not able to cross-check the transaction ID for public key and wallet address.
I am not sure whether it is true or not, but if it is true then what should I do?

Thanks in advance.