HANA Incorrect SUM in aggregation

Hi Experts,

I need to sum up the SalesQty from an Aggregation node which outs the columns as below. Expected SUM of SALESQTY is 28. However, I get the result as 20 because HANA seems to supress duplicates of SALESQTY 4

In the Node Aggregation_Quantity as shown below,Column SUM_SALESQTY is already defined as Aggregated column with "SUM" engine.

However, the result of the below node is 20, while I expect 28. I don't understand what I'm doing wrong here to get the correct sum.

Regards,

Amber