How to create a refund with blank EBS bank account number

We auto create Refund in Receivables reference to Receipt through AR_RECEIPT_API_PUB.ACTIVITY_APPLICATION (p_applied_payment_schedule_id => -8)

And we find if we pass an empty p_bank_account_id into that procedure.  Oracle will default bank account id based on Oracle internal's logic.  But for our case, we need to create a refund with blank EBS bank account number.   Can someone please let us know how to do it automatically?  Or what the best practice for our scenario?  Thanks a lot.

We are using Oracle Receivable 12.1.3