Odoo Debit Notes and Credit Notes

Debit note is issued by Buyer (Customer) to Seller (Vendor) while returning product process. And Seller (Vendor) has to issue Credit note on behalf of that Debit note issued by Buyer (Customer).that 

Customer Invoice -> Create Refund -> This will create Credit note that should be send to Customer.

Supplier Invoice -> Create Refund -> This will create Debit Note that should be send to Vendor.

- A memo sent by one party to inform the other party that a debit has been made to the seller’s (Vendor) account, in buyer’s books, is known as Debit Note. A commercial document which is sent by one party to inform the other party that a credit has been made to buyer’s  (Customer) account, in seller’s books is known as Credit Note. 

Conclusion

Normally, a debit note is issued when there is a return outward (purchase return) while in the case of return inward (sales return) credit note is issued. In a transaction, when the buyer returns the goods to the seller, the buyer will issue a debit note and the opposite party will issue a credit note in exchange for the debit note. Hence, they are the two aspects of the same transaction.