Current behavior:

When a bank statement line is imported into the Payment Reconciliation Journal and multiple open customer ledger entries share the same amount with no document number or external document number match available, the automatic matching engine applies the payment to the newest open entry.

Problem:

This is common with recurring invoicing: a customer billed a fixed amount monthly but paying every two months will regularly have two (or more) open entries of the same amount at the time of reconciliation. Since there's no document number to disambiguate, the engine currently picks the wrong one — the most recent invoice gets settled while the older one stays open. This distorts the customer's aging, can trigger unwarranted overdue reminders or interest on an invoice that is effectively covered by the payment, and requires manual correction on every reconciliation cycle for any customer with this billing pattern.

Proposed change:

When the amount matches one or more open entries but no document/external document number match is found, the automatic application proposal should default to the oldest open entry (by due date or posting date) rather than the newest. This mirrors standard FIFO cash-application logic used elsewhere in the application process and would produce a more accurate default in the common ambiguous case.

Example:

Customer is invoiced €100/month. Payment is received every 2 months, so at reconciliation time there are typically two open €100 entries. A €100 bank line with no document number reference should be proposed against the older of the two invoices, not the most recent one.