[Translation from Japanese to English ] I am very sorry for having sent you a defective item. I had heard that the...

Original text

不良品を送付してしまい、大変申し訳ありませんでした。

購入先からは動作確認済みという話だったのですが、、、
いずれにしても、自分で動作確認をしていなかった私に責任があります。

全額返金させていただきたいと思いますが、いかがでしょうか？

送料がかかるので、商品の返送は不要にしたいと思いますが、
その代わり関税分の返金は免除していただきたいと思います。

よろしくお願い致します。

Translation / English

I am very sorry for having sent you a defective item.

I had heard that the seller had confirmed the behavior of the item had been fine.
But, in either way, I myself am responsible for the defect because I had not checked the item by myself.

I would like to issue a full refund. Would you like to accept it?

As the delivery fee is charged, I would like you to keep the item and not to return the item back to me, but can you please allow me not to make a refund for custom duties?

Thank you in advance.

Translation / English

I am truly sorry for sending you a default product.

I was told by seller that it was inspected..
But if it's not working well, it is my responsibility.

I am willing to refund you the full amount, what do you think?

Returning costs a shipping fee so you don't have to return it, but instead, the I would like to ask you to exclude the custom fee.

Thank you.