How cloudflared read cert.pem in cloudflared

Hi ,
I am parsing cloudflared cert.pem with config map and mounted volume from local but is giving me below error
kubectl logs cloudflared-575dcdfddb-lt48d -n sandbox-backend
ERR Cannot determine default origin certificate path. No file cert.pem in [~/.cloudflared ~/.cloudflare-warp ~/cloudflare-warp /etc/cloudflared /usr/local/etc/cloudflared]. You need to specify the origin certificate path by specifying the origincert option in the configuration file, or set TUNNEL_ORIGIN_CERT environment variable originCertPath=
error parsing tunnel ID: Error locating origin cert: client didn’t specify origincert path

what are the way to read cert.pem in K8.