Manually settle an open invoice, moving it to paid and queueing the receipt document. Use this when payment was collected outside Root; an invoice collected by a Root payment moves to paid on its own when that payment succeeds.
Marking an already-paid invoice as paid is a no-op success, so the call is safe to retry. The line items are left in place, unlike void and mark uncollectible.
A linked Root payment that is still pending is cancelled, so the customer is not collected from twice. One that has already gone to the bank blocks the call with 409; reconcile that payment first.
A credit note can never be marked paid, 409: it is a refund owed to the recipient rather than something they pay, and its status is fixed on creation.
Invoicing is opt-in per organization: unless the invoicing feature flag is enabled for your organization this endpoint returns 403.
The invoice cannot move to paid from its current status. Only an open invoice can be marked paid.
Invoicing is not enabled for the organization, or the caller is missing the invoices:mark_paid permission.
No such invoice, or the caller's user group does not grant access to its policy.
The invoice is a credit note, its linked payment has gone to the bank and can no longer be cancelled, or it was modified by a concurrent writer before the transition could be applied.