foreign key one-to-may doesn't working in blazor wasm net. ore6

Question

Hi, I try to implement the Foreign Key in my app to link several actions,class model ActionItem with main table Developer.
When I run app the ActionItem is null.
Have you some advise ?

you can find github link AppWebFK

When run my app I have the output below. As you can see the ActionItem is well link to Developer via DeveloperId key.

Microsoft.EntityFrameworkCore.Infrastructure: Information: Entity Framework Core 6.0.10 initialized 'ApplicationDBContext' using provider 'Microsoft.EntityFrameworkCore.SqlServer:6.0.10' with options: None  
Microsoft.EntityFrameworkCore.Database.Command: Information: Executed DbCommand (4ms) [Parameters=[], CommandType='Text', CommandTimeout='30']  
  
SELECT [d].[DeveloperId], [d].[ECR], [d].[FEE], [a].[ActionId], [a].[CloseDate], [a].[DescriptionA], [a].[DeveloperId], [a].[OpenDate], [a].[PlanDate], [a].[State], [a].[Tilte]  
  
FROM [Developers] AS [d]  
LEFT JOIN [ActionItems] AS [a] ON [d].[DeveloperId] = [a].[DeveloperId]  
ORDER BY [d].[DeveloperId]