Refund period
保退期

Excuse me, miss. I don't think we need the MP4 anymore. We would like to refund it.
打扰一下，小姐，我觉得我们不需要这台MP4了，我们想退货。
May I see your receipt?
我能看看您的发票吗？

Here you are.
给你。
I am sorry, sir. You bought it 2 weeks ago. And you can only refund it in one week.
抱歉，先生，您是两周前买的这台MP4，保退期只有一个星期。