When to unallocate payments and credit notes from invoices:

• Edit or Delete an Invoice. When allocated to a payment or credit note
• Incorrect Allocation. If you've allocated the payment or receipt incorrectly

Unallocating a transaction breaks the link between an invoice and a payment. Do this if you matched a payment to the wrong invoice or need to delete or edit it.

Once unallocated:

• Update the Invoice. Mark it as unpaid
• Save the Payment. Record it as a payment on account to match with another invoice
• Customer or Supplier Account. Keep the balance the same
• Bank Account. Maintain the same balance

 NOTE: Unallocating a transaction doesn't remove it from the bank reconciliation. 

• Unallocate sales transactions
• Unallocate purchase transactions