Microsoft.Graph 5.75.0 graphServiceClient.Users[userId].Calendar.Events.GetAsync() throwing Microsoft.Kiota.Abstractions.ApiException: The server returned an unexpected status code and the error registered for this code failed to deserialize: 503

[mghabin]

Hello,

Details:

• Multiple tenants affected.
• Multiple users affected.
• Microsoft.Graph 5.75.0
• Method used: graphServiceClient.Users[userId].Calendar.Events.GetAsync()
• Calls made using delegated permissions (The tenants admins consented, and service principle is living in the customer tenant with right permissions)
• Issue started to happen in last month and we don't want this to grow.

Code used:

private readonly string defaultExpandExtendedProperties = $"singleValueExtendedProperties($filter=" +
     $"id eq '{ExtendedPropertyIds.A}'" +
     $"or id eq '{ExtendedPropertyIds.B}'" +
     $")";

var filterParts = new List<string>
{
    $"start/dateTime ge '{startUtc}'",
    $"start/dateTime lt '{endUtc}'",
    $"singleValueExtendedProperties/Any(p: p/id eq '{ExtendedPropertyIds.A}' and p/value eq '{AValue}') " +
    $"or singleValueExtendedProperties/Any(p: p/id eq '{ExtendedPropertyIds.B}' and p/value eq '{BValue}')",
};
var events = await graphServiceClient.Users[userId].Calendar.Events.GetAsync((requestConfiguration) =>
{
    requestConfiguration.Headers.Add("Prefer", $"outlook.timezone=\"{timeZone}\"");
    requestConfiguration.QueryParameters.Expand = [this.defaultExpandExtendedProperties];
    requestConfiguration.QueryParameters.Top = 50;
    requestConfiguration.QueryParameters.Filter = string.Join(" and ", filterParts);
    requestConfiguration.QueryParameters.Select = ["id", "subject", "body", "bodyPreview", "start", "end", "organizer", "attendees", "singleValueExtendedProperties", "recurrence", "onlineMeeting", "originalStartTimeZone", "type"];
});

Results in:

Microsoft.Kiota.Abstractions.ApiException: The server returned an unexpected status code and the error registered for this code failed to deserialize: 503    at Microsoft.Kiota.Http.HttpClientLibrary.HttpClientRequestAdapter.ThrowIfFailedResponseAsync(HttpResponseMessage response, Dictionary`2 errorMapping, Activity activityForAttributes, CancellationToken cancellationToken)    at Microsoft.Kiota.Http.HttpClientLibrary.HttpClientRequestAdapter.SendAsync[ModelType](RequestInformation requestInfo, ParsableFactory`1 factory, Dictionary`2 errorMapping, CancellationToken cancellationToken)    at Microsoft.Kiota.Http.HttpClientLibrary.HttpClientRequestAdapter.SendAsync[ModelType](RequestInformation requestInfo, ParsableFactory`1 factory, Dictionary`2 errorMapping, CancellationToken cancellationToken)    at Microsoft.Graph.Users.Item.Calendar.Events.EventsRequestBuilder.GetAsync(Action`1 requestConfiguration, CancellationToken cancellationToken)   at **Reducted**

Please help us solving this as customers panics from this to grow.