MetricAlertAtResourceGroupLevel operation not working in Microsoft.Insights/metricAlerts Get call

Hi,

I am trying to get all the metric alerts at resource group level using Get operation mentioned in the below document.

https://docs.microsoft.com/en-us/rest/api/monitor/metricalerts/get#get_an_alert_rule_on_resource_group(s)

From the document, only get on single metric alert works. All the other Get operations like MetricAlertAtResourceGroupLevel, MetricAlertAtSubscriptionLevel MetricAlertOnMultipleResources are not working.

Api_version used : 2018-03-01

Start with the linked Metric Alerts REST API documentation and the 2018-03-01 API version. Reproduce the Get calls for resource-group, subscription-level, and multiple-resource alerts, recording the requests and errors; the work is done when the affected operations are either corrected or the documentation clearly matches their supported behavior.

Written by the indexing model from the issue text.