Error while settling Commodity futures 70D while TBB1

Question

Hi
We are getting both profit as well as loss when we run TBB1 for settlement of Commodity futures
for Product type 70D.
We have added brokerage, service tax in other flows both in purchase and sale transaction.
The other flows of purchases are coming as loss and other flows from sales transaciton are
getting reduced from the profits. We understand some issue with DBT_B020 (Derived flow for
Variation margin Loss).
We are expecting the other flows of purchase transaciton to be deducted from profits as it is
doing for other flows of sale transaciton.
Wanted to check here whether any config needs to be done to arrive at this.
Example
Purchase transaction
Purchase value Rs 1,00,000-
Other flows      Rs    2,000-
Total cost     Rs 1,02,000-
Sale transaciton
Sale value     Rs 1,20,000+
Other flows    Rs    2,000-
Total cost     Rs 1,18,000+
But we are getting two entries
1. Profit on sale  Dr.       Rs 18,000
      To. Margin Variantion  Rs 18,000
And
2. Margin Variantion  Rs 2,000
       T0. Loss on sale   Rs  2,000
When we run TBB1 we expect only one entry for profit of Rs. 16,000
Regards
Venkat

Answer 1