There's one of two ways that these payments can appear against the Customer:
Case 1. The Payment is allocated against an Invoice in the Business System.
When the payment is allocated, the payment amount is simply deducted from the Invoice. No document appears in Forecast.Live because the invoice is not outstanding
Case 2. The payment is not allocated to an Invoice yet.
An unallocated payment from a Customer will show as a net-negative outstanding invoice from that Customer

Tip: You can go to the Unallocated Invoices report to see potential invoice matches for reconciliation to reduce this list.
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