Why my OData url don't work ?

Hi

I have an OData feed who work perfectly but not in a particular configuration. I work on Dynamics 365 CRM and can obtain all tables since :

"https://{MY_SITE}.api.crm4.dynamics.com/api/data/v9.1/"

and contacts Attributes with

https://{MY_SITE}.api.crm4.dynamics.com/api/data/v9.0/EntityDefinitions(LogicalName='contact')?$select=LogicalName&$expand=Attributes($select=LogicalName;$filter=AttributeType eq Microsoft.Dynamics.CRM.AttributeTypeCode'Picklist')

but not since

https://{MY_SITE}.api.crm4.dynamics.com/api/data/v9.0/EntityDefinitions(LogicalName='contact')/Attributes/Microsoft.Dynamics.CRM.PicklistAttributeMetadata?$select=LogicalName&$expand=OptionSet,GlobalOptionSet

I've followed all instruction on https://docs.microsoft.com/fr-fr/dynamics365/customer-engagement/developer/webapi/query-metadata-web-api but it don't work.

Someone can say why? I would like to get OptionList attributes but it was not present in table GlobalOptionSetDefinition

The complete code in M in power query :

let
    Source = OData.Feed("https://{MY_SITE}.api.crm4.dynamics.com/api/data/v9.0/EntityDefinitions(LogicalName='contact')?$select=LogicalName&$expand=Attributes($select=LogicalName;$filter=AttributeType eq Microsoft.Dynamics.CRM.AttributeTypeCode'Picklist')", null, [Implementation="2.0", Headers = [Accept = "application/json"]]),
    Attributes = Source[Attributes]
in
    Attributes

Thanks