IEX: Scoring Engine Harness program not working for Bill to level

We are assigned strategies at Operating unit Bill to Level. As per business need we have created scoring components for Amount determination and for Aging bucket for line.

The ask is as follows:

If amount is <500 - Level 1

Amount >500 to <1000 - Level 2

Amount >1000 - Level 3

Age days as follows

Past due 1 - 30 days

Past due 31 - 60 days

Past due 61 - 9999 days

We are unable to handle a cases combination of Aging+amount for Bill to site and scoring is not coming correct.

Example: How to handle a case where amount is < 500 and delinquent transactions are spread across multiple aging days? If we sum the amount and max the aging days then the scoring is not correct. Like multiple combination of cases, how to handle per bill to site?