❔ API doesnt return dynamic object in ASP.NET Core 2.0

I am looking to return a list from a Dynamic linq query but the problem comes when returning the list it doesnt return anything on swagger

the code is like

       var result = _ctx.AccionFormativa
                         .Include(x => x.OfertaFormativa)
                         .Include(x => x.Modalidad)
                         .Include(x => x.ProgramasFormacion)
                         .Include(x => x.StatusCurso)
                         .Include(x => x.Centro)
                         .ThenInclude(x => x.DireccionCentro)
                         .Include(x => x.Ambito)
                         .GroupBy(fields, "it")
                         .ToDynamicList()
                         .Select(x => (new DynamicExpando(x)).GetCurrentObject);