Hope you are doing well.
Generally, this issue will occur If a status code other than 200 or 404 is returned from a provider or if a provider times out. If successful, this method returns a
200 OK response code and collection of alert objects in the response body.
Please refer this doc for more det: https://learn.microsoft.com/en-us/graph/api/alert-list?view=graph-rest-1.0&tabs=http
The response will be a
206 Partial Content status code with the provider's response in a warning header. For more information, see Microsoft Graph Security API error responses.
Hope this helps.
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