$expand parameter not expanding the navigation property in EDM

Metadata has a navigation property Organization shown below :

https://localhost:34345/api/Users/$metadata#Collection(Model)

<?xml version="1.0" encoding="utf-8"?> <edmx:Edmx Version="4.0" xmlns:edmx="http://docs.oasis-open.org/odata/ns/edmx"> <edmx:DataServices> <Schema Namespace="Model" xmlns="http://docs.oasis-open.org/odata/ns/edm"> <EntityType Name="User"> <Key> <PropertyRef Name="UserId" /> </Key> <Property Name="UserId" Type="Edm.String" Nullable="false" /> <Property Name="FirstName" Type="Edm.String" Nullable="false" /> <Property Name="LastName" Type="Edm.String" Nullable="false" /> <NavigationProperty Name="Organization" Type="Collection(Model.UserOrganization)" /> </EntityType> <EntityType Name="UserOrganization"> <Key> <PropertyRef Name="OrganizationId" /> <PropertyRef Name="UserId" /> </Key> <Property Name="OrganizationId" Type="Edm.String" Nullable="false" /> <Property Name="UserId" Type="Edm.String" Nullable="false" /> <Property Name="OrganizationName" Type="Edm.String" /> <Property Name="IsLocked" Type="Edm.Boolean" Nullable="false" /> <Property Name="Email" Type="Edm.String" /> <Property Name="MobilePhoneNumber" Type="Edm.String" /> <Property Name="OfficePhoneNumber" Type="Edm.String" /> </EntityType> </Schema> <Schema Namespace="Default" xmlns="http://docs.oasis-open.org/odata/ns/edm"> <EntityContainer Name="Container"> <EntitySet Name="User" EntityType="Model.User"> <NavigationPropertyBinding Path="Organization" Target="Organization" /> </EntitySet> <EntitySet Name="Organization" EntityType="Model.UserOrganization" /> </EntityContainer> </Schema> </edmx:DataServices> </edmx:Edmx>

EDM Conventional Model Builder:

ODataConventionModelBuilder builder = new ODataConventionModelBuilder(); builder.EntitySet<User>(DataConstant.User);

Startup.cs - IApplicationBuilder configure :
`private static void MapOdataRoutService(IApplicationBuilder appBuilder)
{

appBuilder.UseMvc(odata =>
{

odata.EnableDependencyInjection();

odata.Select().Expand().Filter().OrderBy().MaxTop(null).Count();

         odata.MapODataServiceRoute(DataConstant.UserControllerName, "api/Users", GetUserEdmModel());
  }

}`

LINQ select query to return IQueryable of User, here User and UserOrganization are DTO's manually mapping property from dbsets (users, userOrganizations)

`
return Task.FromResult((from user in users
select new User
{
FirstName = user.FirstName,
LastName = user.LastName,
UserId = user.UserId,
Organization = (from organization in userOrganizations
where organization.UserId == user.UserId
select new UserOrganization
{
UserId = organization.UserId,
OrganizationId = organization.OrganizationID,
OrganizationName = organization.OrganizationName,
IsLocked = organization.IsLocked,
Email = organization.Email,
MobilePhoneNumber = organization.MobilePhoneNumber,
OfficePhoneNumber = organization.OfficePhoneNumber,

                                                    }).ToList()
                                }));`

API URL with $Expand not showing up the organization collection in the api result :

https://localhost:34345/api/Users?$expand=Organization

{ "@odata.type": "#Model.User", "UserId": "XXX-XXXX-XXXX", "FirstName": "F", "LastName": "L" }

Other parameters like $top, $count, $filter and $select on the available fields are works good.

Used packages:

.NET 5
Microsoft.AspNetCore.OData 7.5.5
Microsoft.EntityFrameworkCore 5.0.1
Microsoft.EntityFrameworkCore.SqlServer 5.0.1
Microsoft.EntityFrameworkCore.Tools 5.0.1

Any idea on how to get the expanded result?

Thanks in advance!

Start with Startup.cs, especially MapOdataRoutService and GetUserEdmModel, then inspect the LINQ projection that populates User.Organization. Reproduce the request at /api/Users?$expand=Organization and compare it with the EDM metadata; done means the response includes the expanded Organization collection without breaking the working query options.