Sender email address for Customer Account Statement

Dear Experts,

Here's an issue that my colleague and I are currently facing:-

The Customer Account Statements that are sent via email in the transaction F.27 show that the sender email address is not equals the Accounting Clerk (KNB1-BUSAB) maintained in customer master data (FD03). Instead, the sender email address here is the email address of the person executing the transaction F.27.

I've looked through some programs (RFKORK00 and RFKORD10), and the variant used (SAPMA). Unfortunately, we still could not determine the root cause for this issue. What should we be looking into, and how can we resolve this issue too?

Any inputs would be much appreciated. Thanks.

Regards,

Deborah