private async void Screen_Tick(object sender, EventArgs e) { lstbxFinished.Items.Clear(); lstbxProcessing.Items.Clear(); List <Order> InProcessOrders = (await _repo.GetInProcessOrderssAsync(1)).ToList(); List <Order> finishedOrders = (await _repo.GetFinishedOrdersAsync(1)).ToList(); InProcessOrders.ForEach(a => lstbxProcessing.Items.Add(a.OrderID)); finishedOrders.ForEach(a => lstbxFinished.Items.Add(a.OrderID)); }