Most businesses chase payments the same way: they look at a customer's total balance and say "they owe this much". But that is not the real question. If part of that 50,000 comes from an invoice issued this month and part from one issued eight months ago, they are not the same risk.
What works is splitting receivables by age: not yet due, up to 30 days late, up to 60 days late, and older. Who you need to call this week then becomes obvious by itself.
The second thing that matters is that the report reflects payments actually received. If a partly paid invoice still shows its full amount, the report is misleading you. Kumpara's ageing report works on the remaining amount: fully paid invoices drop off the list, and a half-paid invoice appears only with what is left.