Got the same email yesterday. If you read that email again, you will find the font of the content is different from her name/photo at the end of the message. I think it is a scam. Only 32 feedbacks. Last one is over 1 year.
you can refund part of the amount via PayPal. Just click the refund link in that transaction. In the next page, you can enter the amount. PayPal will also return the fee for that part.