Advanced Pricing Custom qualifier context

Team,

I have a requirement, where i need to charge customer a delivery charge of $35.00 in the below condition

1) Shipping Method = Our Truck, 2) Freight Terms = Non Exempt and 3) order total between $1  and $399.99.

For the 3rd condition i created a custom qualifier "ORDER TOTAL" under ORDER  and assigned the below function, when i assign the first 2 conditions modifier is getting applied successfully, however when i add this 3rd condition i am having problem to get the delivery charge applied. (Attached are the screen shots for reference)

   FUNCTION get_order_total (p_header_id IN NUMBER)

      RETURN NUMBER

   IS

      l_order_sum   NUMBER;