There is no specified function in DPS FD for calculating or posting Interest on late payment of bills.
Please check with your accountants on how they would like to record this. An example of how to record this would be as follows:
Notify the client in writing of the penalty interest on late payment of your bill.
Upon receipt of the funds from the client go to Nominal Ledger.
Select Bank Payments and Receipts.
Select type as Bank Receipt.
Complete fields and select a relevant nominal to assign the receipt to, then Post Batch.