title: cert manager is failing with Waiting for dns-01 challenge propagation: Could not determine authoritative nameservers
body: <p>I have created cert-manager on aks-engine using below command 
  kubectl apply --validate=false -f <a href="https://github.com/jetstack/cert-manager/releases/download/v0.12.0/cert-manager.yaml" rel="nofollow noreferrer">https://github.com/jetstack/cert-manager/releases/download/v0.12.0/cert-manager.yaml</a></p>
  
  <p>my certificate spec</p>
  
  <p><a href="https://i.stack.imgur.com/8jRUw.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/8jRUw.png" alt="enter image description here"></a></p>
  
  <p>issuer spec </p>
  
  <p><a href="https://i.stack.imgur.com/foRDW.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/foRDW.png" alt="enter image description here"></a></p>
  
  <p>Im using nginx as ingress, I could see txt record in the azure dns zone created my azuredns service principle, but not sure what is the issue on nameservers</p>