RadzenDropDownDataGrid with int ValueProperty

hi,
I am trying to use RadzenDropDownDataGrid with int ValueProperty but it gives me an error and tried to cast int to string but same error (System.InvalidCastException: Specified cast is not valid.) any idea how to solve this as I need ValueProperty and Change="@(args => multipleValues = args ? parts.Select(c => c.PartsID): multipleValues = Enumerable.Empty())" /> should be int.
also when I click on check box the check box does not checked.

<RadzenDropDownDataGrid AllowFiltering="true" FilterCaseSensitivity="FilterCaseSensitivity.CaseInsensitive" ColumnWidth="200" TabIndex="1" Visible="true" AllowClear="true" @bind-Value=@multipleValues
                                          TValue="IEnumerable<string>"  Multiple="true" Placeholder="Select..." Data=@parts TextProperty="PartsValue" ValueProperty="PartsID"
                                            Change=@(args => OnChange(args, "DropDownDataGrid with multiple selection")) Style="width:400px">
                        <Columns>
                            <RadzenDropDownDataGridColumn Width="40px" Sortable="false">
                                <HeaderTemplate>
                                    <RadzenCheckBox TriState="false" TValue="bool" Value="@(parts.Any(c => multipleValues != null && multipleValues.Equals(c.PartsValue)))"
                                                    Change="@(args => multipleValues = args ? parts.Select(c => c.PartsID): multipleValues = Enumerable.Empty<string>())" />
                                </HeaderTemplate>
                                <Template Context="data">
                                    <RadzenCheckBox TriState="false" Value="@(multipleValues != null && multipleValues.Equals(((Parts)data).PartsID))" />
                                </Template>
                            </RadzenDropDownDataGridColumn>
                           
                            <RadzenDropDownDataGridColumn Property="PartsValue" Title="PartsValue" Width="200px" />

                        </Columns>
                    </RadzenDropDownDataGrid>


void OnChange(object value, string name)
                    {
                       var str = value is IEnumerable<object> ? string.Join(", ", (IEnumerable<object>)value) : value;
                     
                        StateHasChanged();
                    }

If this was copied from our demo you will need to adapt to your. Like the part I’ve quoted. Check your code.

it is already there .... but same error.
also the checkbox doesn't checked.