Pods failing with "no IP addresses available in range set" and "failed to send CNI request" errors in OpenShift 4

Issue

• The application and default OCP pods creation fail with below error.

  error configuring pod [namespace/test-pod] networking: [namespace/test-pod/20feddxxxxxx:openshift-sdn]: error adding container to network "openshift-sdn": CNI request failed with status 400: 'failed to run IPAM for 318932a1xxxxxxx: failed to run CNI IPAM ADD: failed to allocate for range 0: no IP addresses available in range set: 10.x.x.x-10.x.x.x
  
  error adding pod namespace/test-pod to CNI network "multus-cni-network": plugin type="multus-shim" name="multus-cni-network" failed (add): CmdAdd (shim): failed to send CNI request: Post "http://dummy/cni": dial unix /run/multus/socket/multus.sock: connect: connection refused
  

• Pods are failing with the error no IP addresses available in range set despite having sufficient IPs available in the cluster.