renew certificate using this command

openssl x509 -req -in data-prepper-ingress.csr -CA $ROOT_CA_CERT -CAkey $ROOT_CA_KEY -CAcreateserial -out data-prepper-ingress.crt -days 365 -sha256 -extfile data-prepper-ingress.cnf -extensions server_extensions



k delete secret -n observability dataprepper-ingress-tls

then create kubernetes secret

k create secret --namespace observability tls dataprepper-ingress-tls --cert=data-prepper-ingress.crt --key=data-prepper-ingress.key --dry-run=client -o yaml | k apply -f -

verify 

k get secret -n observability dataprepper-ingress-tls -o jsonpath='{.type}{"\n"}'

is should say kubernetes.io/tls

kubectl get secret dataprepper-ingress-tls \
  -n observability \
  -o jsonpath='{.data.tls\.crt}' |
base64 -d |
openssl x509 -noout -subject -issuer -ext subjectAltName