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You can leave the Documents tab empty: in this case, the credit note itself can be used as credit (advance) for future supplies or as the basis for refunding the customer.
The "Credit Note (create)" form. The Documents tab
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In the Business Activity column, select the business activities to which the documents are related.
In the Expense Item column, select the item from the Expense Items list to link the expense incurred from this adjustment.
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