Error on add row script in subform

Error on add row script in subform

Hi,

I am using a subform called Order_Details to enter the products and quantities on a Purchase Order form.

In order to filter product availability by Supplier, I have written the following script which runs "on add row". 

itemlist  =  Winery_Supplies  [Contacts == input.Contacts];
clear row.Product;
row.Product:ui.append(itemlist.Winery_Product_Name.getall());


The script is filtering the products by supplier in the Product field but the following error appears when a row is added in the subform:

"Error Details

Error occured while executing on add row script."

If I close the error message, I can continue to enter data.

I would be most grateful for any guidance on eliminating this error.

Best regards,

Jeff