Update container-insights-prometheus-metrics-addon.md

Author: bragi92

articles/azure-monitor/containers/container-insights-prometheus-metrics-addon.md

@@ -268,7 +268,9 @@ ama-metrics-ksm-5fcf8dffcd      1         1         1       11h
 
 
 ## Uninstall metrics addon
-Currently, Azure CLI is the only option to remove the metrics addon and stop sending Prometheus metrics to Azure Monitor managed service for Prometheus. The following command removes the agent from the cluster nodes and deletes the recording rules created for the data being collected from the cluster, it doesn't remove the DCE, DCR, or the data already collected and stored in your Azure Monitor workspace.
+
+Currently, Azure CLI is the only option to remove the metrics addon and stop sending Prometheus metrics to Azure Monitor managed service for Prometheus.
+The aks-preview extension needs to be installed using the command `az extension add --name aks-preview`. For more information on how to install a CLI extension, see [Use and manage extensions with the Azure CLI](/azure/azure-cli-extensions-overview). The following command removes the agent from the cluster nodes and deletes the recording rules created for the data being collected from the cluster, it doesn't remove the DCE, DCR, or the data already collected and stored in your Azure Monitor workspace.
 
 ```azurecli
 az aks update --disable-azuremonitormetrics -n <cluster-name> -g <cluster-resource-group>