Fetch ItemSerialNumber in a Field of Form

Hi Team,

We have a requirement to fetch ItemSerialNumber linked to an Affected User. Using below query in form but getting error. Please help.

select Item.serialNumber from item as Item where (Item.product.productClass.shortCode='CELL' and Item.user.id = @*@$new.affectedUser.id@*@) 

Thanks,

Manish Verma