Here's the code I'm using. Nothing seems to work. Instead of adding and subtracting the inventory it only inserts the number in my text box. Instead if should add or subtract from the inventory. Any help is much appreciated.
Patch(
tblOptrackInventoryImportedDataCSVS,
LookUp (
tblOptrackInventoryImportedDataCSVS,
FORM_NO = ddl_Form_No.Selected.Value && WAREHOUSE = ddl_From_Warehouse.Selected.Value
),
{ON_HAND: Value("ON_HAND") - Value(txtQuantity.Text)}
);