IBAN and Swift Code not getting transferred to bank for payment

Hello Experts,

IBAN code is maintained in vendor master bank details and the swift code is also maniatined in bank key. IBAN and Swift codes are also reflected in DME file and status showing transferred but it reaches to bank without the IBAN code.What could be the reason? Has it something to do with the IBAN check box in FBZP, which is unchecked for payment method on country level? Do we have to map these fields in DME engine? Where is the IBAN code fetched from into the DME file? Is there any lateral filteration happening while this file is transferred to the bank for payment? I believe, the IBAN code in the house bank and the one in vendor master are different,rightly. House bank IBAN is of the paying entity and the IBAN in vendor master is specific to the vendor.

Please guide how to map these missing fields in DME engine.

Appreciate an early response.

Regards

Partha