GraphQL disposed DataContext

When trying GraphQL in the Playground, I get the following error:

Cannot access a disposed context instance. A common cause of this error is disposing a context instance that was resolved from dependency injection and then later trying to use the same context instance elsewhere in your application. This may occur if you are calling ‘Dispose’ on the context instance, or wrapping it in a using statement. If you are using dependency injection, you should let the dependency injection container take care of disposing context instances.nObject name: ‘MyDataContext’."

In my .net Project I have a Program.cs file, which registers the Interfaces/DataContext as follows:

builder.Services.AddAdvancedDependencyInjection();
builder.Services.Scan(p => p.FromAssemblies(assemblies)
    .AddClasses()
    .AsMatchingInterface());

builder.Services.AddDbContext<MyDataContext>();

builder.Services.AddGraphQLServer()
    .AddQueryType<MyDataQuery>()
    .AddFiltering()
    .AddSorting()
    .ModifyRequestOptions(opt => opt.IncludeExceptionDetails = true);

In my MyDataQuery.cs I load the data from the IDataService as follows.

class MyDataQuery 
{
    private readonly IDataService _dataService;

    public MyDataQuery(IDataService dataService) 
    {
         _dataService = dataService;
    }

    [UsePaging]
    [HotChocolate.Types.UseFiltering]
    [HotChocolate.Types.UseSorting]
    public async Task<IQueryable<Data>> Data() 
    {
        var data = _dataService.GetData();
        data.ToList(); // Code breaks here, because the dataContext is disposed.

        // some async stuff. 
    }
}

My Service looks like this:

public class DataService : IDataService
{
    public readonly MyDataContext _context;

    public DataService (MyDataContext context)
    {
        _context = context;
    }

    public IEnumerable<Data> GetData()
    {
        return _context.Data;
    }
}

When I use the IDataService at other points, that are entered via a controller, everything works fine.
How should I register the Service/DataContext to make GraphQL work?