I was trying to create an AKS cluster and it failed with the following message in the portal

{
    "status": "Failed",
    "error": {
        "code": "ResourceDeploymentFailure",
        "message": "The resource operation completed with terminal provisioning state 'Failed'.",
        "details": [
            {
                "code": "ReconcileStandardLoadBalancerError",
                "message": "Reconcile standard load balancer failed. Details: standardLoadBalancerReconciler retry failed: Code=\"SubscriptionNotRegistered\" Message=\"Subscription xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx is not registered with NRP.\" Details=[]."
            }
        ]
    }
}