I am trying to get the url for an image from my "updates" node in Umbraco. All other data is displaying perfectly, but the image url just says NULL. I can get the ID of the image, by removing the URL at the end.

Do you have any idea about what im doing wrong?

using System.Collections.Generic;
using System.Threading.Tasks;
using System.Web.Http;
using crossmind.dk.Models;
using Umbraco.Core.Models;
using Umbraco.Web;
using Umbraco.Web.WebApi;

namespace crossmind.dk.Controllers
{
    public class UpdateApiController : UmbracoApiController
    {
        [HttpGet]
        public async Task<IHttpActionResult> GetAllUpdates()
        {
            var updateList = new List<Update>();
            var updates = UmbracoContext.ContentCache.GetById(1061).Children();

            foreach (var updateItem in updates)
            {
                updateList.Add(new Update
                {
                    Title = updateItem.Name,
                    Date = updateItem.CreateDate.ToString("D"),
                    Url =  updateItem.Url,
                    ImageUrl = updateItem.GetPropertyValue<IPublishedContent>("billede")?.Url()
                });
            }
            return Ok(updateList);
        }
    }
}

Thanks in advance, Andreas.