Validation for ListBox not working

I have the following listbox with validator that will not validate properly. It shows invalid no matter if it is empty or populated. The only way I can get it to validate is to select an item in the listbox. If it helps LBvalue seems to always be null even when I select an item. Any Ideas?

<RadzenListBox class="form-control form-text-custom" Name="LBDates" @bind-Value=@LBvalue Data="@dates" Style="height:115px; width:205px" Change=@(args => OnLBChange(args, "ListBox"))></RadzenListBox>

<RadzenRequiredValidator Component="LBDates" Text="Atleast 1 date is required" Popup="true" Style="position: relative;" />

Since i got no bites I guess i should rephase my question:

How do I validate a listbox and a select? Can it be done? I've tried the required and length validator and neither work. Can someone post an example?

Here is a minimal example based on our demo:

 <RadzenTemplateForm Data=@("Data")>
     <RadzenListBox Name="Customer" @bind-Value=@value Data=@customers 
        TextProperty="CompanyName" ValueProperty="CustomerID"/>
     <RadzenRequiredValidator Text="Customer is required" 
        Component="Customer" />
     <RadzenButton ButtonType="ButtonType.Submit" Text="Save" />

@code {
    string value = null;
    IEnumerable<Customer> customers;

    protected override void OnInitialized()
        customers = dbContext.Customers.ToList();