是用邮件写出来，大致就是这个样子。我随便写写，英文好的朋友可以继续优化：
Dear Michael,
I’m really sorry to inform you that the delivery time should be delayed two weeks.
In reality, we found some minor scratches on the body surface during our internal inspection. Please check the photos in attachment.
We understand it is essential to ship the goods on time. But we cannot lay off this issue. We take the quality as priority and cannot sell any defective items to our customers, even a minor problem.
Therefore, I plan to arrange the full inspection soon, to assure the quality for these products. And the updated ETD is 16th May.
Furthermore, a 3% discount will be provided in the next order, to say a big SORRY to you.
