Void a payment

post https://gateway.stage.bill.com/connect/v3/payments/{paymentId}/void

Void an existing payment.

Void a bill payment that has started processing and cannot be canceled (with POST /v3/payments/{paymentId}/cancel). You can attempt to void payments made both with BILL (online) and outside BILL (offline).

Void a payment made with BILL (online)

In your /POST /v3/payments/{paymentId}/void request:

Set paymentId as the BILL-generated ID of the payment. The value begins with stp.
Set type as the void payment request type
Set reason as the reason for voiding the payment

See Can I cancel or void a Payables payment? in the BILL Help Center to learn about the BILL void payment process and timing in the production environment.