1. If the original invoice can be recovered, the recovered original invoice shall be regarded as invalid. In case of full refund, a refund invoice shall be re-issued according to the original invoiced amount; For the refund of the difference, the invoice shall be reissued according to the actual amount received, and the reissued bookkeeping copy and the recovered original invoice shall be used as the bookkeeping basis for offsetting the income.

Two, if you can't recover the original invoice, according to the following measures:

1. When the refund is re-invoiced, the payee should fill in the "Item" column of re-invoicing and invoice the payer according to the actual refund amount.

2. The payee shall submit the accounting copy of the reissued refund invoice and a copy of the original invoice, or the written materials such as the invoice number, password, project content and amount of the original invoice to the competent tax authorities for examination and approval. After the audit, the taxpayer shall sign an opinion and affix a seal on the back of the re-issued invoice accounting joint as the basis for accounting treatment.

I hope it helps you.