delete
https://api.sandbox.hint.com/api/provider/customer_invoices/
Allowed for a draft invoice, and for a cancelled (voided) or zero-total invoice that has no
payments. Any other invoice fails with
400 This customer invoice cannot be deleted because it still has financial impact. Draft, void or zero dollar invoices can be deleted.
Deleting an invoice also deletes its charges and returns the quantities they consumed
(coverage allowance, prepaid package items, charge-item inventory).
204No content

