How to query sharepointdocument entity from C# ?

Hello everybody,

SharePoint has been integrated in our Dynamics CRM Online (Settings > Document Management then Enable server-based SharePoint integration, etc...) and enabled for a few entities (i.e. contact or account).

I can query sharepointdocument entity with XrmToolbox

<fetch top="50">
  <entity name="sharepointdocument">
    <filter type="and">
      <condition attribute="regardingobjecttypecode" operator="eq" value="2" />
      <condition attribute="regardingobjectid" operator="eq" value="1053ec5b-b4ab-ed11-83fe-000d3a959720" uiname="Klee Paul" uitype="contact" />
    </filter>
  </entity>
</fetch>

But the same query doesn't work from a .net core 6.0 application / Microsoft.PowerPlatform.Dataverse.Client latest stable (1.0.39), either console or webapp.

            string fetchquery =
                @"<fetch version='1.0' output-format='xml-platform' mapping='logical' distinct='false'>
                      <entity name='sharepointdocument'>
                        <filter type='and'>
                          <condition attribute='regardingobjecttypecode' operator='eq' value='2' />
                          <condition attribute='regardingobjectid' operator='eq' value='1053ec5b-b4ab-ed11-83fe-000d3a959720' uiname='Klee Paul' uitype='contact' />
                        </filter>
                      </entity>
                </fetch>";

            EntityCollection list = _svcClient.RetrieveMultiple(new FetchExpression(fetchquery));
            foreach (Entity entity in list.Entities) {
                // do something
            }

or with QueryExpression

            QueryExpression query = new QueryExpression("sharepointdocument");
            query.ColumnSet = new ColumnSet(true);
            var filter = new FilterExpression();

            filter.AddCondition(new ConditionExpression("regardingobjecttypecode", ConditionOperator.Equal, 2));
            Guid contactId = Guid.Parse("1053ec5b-b4ab-ed11-83fe-000d3a959720");
            filter.AddCondition(new ConditionExpression("regardingobjectid", ConditionOperator.Equal, contactId));

            query.Criteria = filter;
            query.AddOrder("fullname", OrderType.Ascending);

            EntityCollection list = _svcClient.RetrieveMultiple(query);
            foreach (Entity entity in list.Entities) {
                // Do something
            }

The error is

Unhandled exception: System.ServiceModel.FaultException`1[Microsoft.Xrm.Sdk.OrganizationServiceFault] : At least 1 Claim must not be NULL, current claims are : nameid=;nii=urn:federation:microsoftonline (le détail de l'erreur est égal à Exception details:
ErrorCode: 0x80040216
Message: At least 1 Claim must not be NULL, current claims are : nameid=;nii=urn:federation:microsoftonline

Then I tried to set _svcClient.CallerId with admin user (which was not necessary in other queries in my app) but same error.

Am I missing something ? Is there a way to query sharepointdocument from C# ?

Thanks in advance !