What does one lump-sum payment across several utility accounts look like in practice?

A utilities retailer receives a single bank credit of 1,860.00 with the reference 'ACCT 44120 + 44121 + 44187 Q3'. It is logged as `RCPT-7731`. The payer is a property manager who holds three electricity accounts.

The collections analyst opens the accounts. `ACCT-44120` has an open bill of 640.00, `ACCT-44121` has 590.00 and `ACCT-44187` has 700.00. The bills total 1,930.00, so the payment is 70.00 short.

Policy `POL-SHORT-01` says a short payment is applied bill by bill in the order listed on the reference, with any shortfall landing on the last account. The analyst applies 640.00 to 44120, 590.00 to 44121 and 630.00 to 44187, leaving 70.00 open on 44187. A reminder for that balance is scheduled, and the analyst raises `CASE-0412` asking the property manager which account the shortfall was meant for.

Two days later the property manager replies that the shortfall belongs to 44121. The analyst reverses the allocations on 44121 and 44187, applies 520.00 to 44121 and 700.00 to 44187, and cancels the reminder on 44187 before it is sent. A correct reminder now applies to 44121.

**Consequence.** Had the first allocation stood, a reminder would have gone to a customer who had paid that account in full.

**What it teaches.** A correct result depends on policy order, exact arithmetic and a documented query. The allocation must also be reversible, with downstream triggers kept in step.