Unable to join raft leader from vault-1 pod in k8s

error during raft bootstrap init call: Put "https://vault-0.vault-internal:8200/v1/sys/storage/raft/bootstrap/challenge\“: tls: failed to verify certificate: x509: certificate signed by unknown authority”
2025-02-06T05:53:29.830Z [ERROR] core: failed to join raft cluster: error=“failed to get raft challenge” does anyone also faced this issue … i have all certs signed by my self created CA authroity , certs are mounted in pod also but still this error