請幫忙看看這個是怎麽回事？

之前有人買東西從我這裏，我也寄出了，但是突然收到paypal來信說要此次交易review 然後直接從帳戶上把錢扣回去了:

We were recently notified that a payment you received was reversed by the buyer’s bank. A bank reversal can be requested by the bank itself or the bank account holder.

40064251386245923

We have placed a temporary hold on the funds until our inquiry is complete.

We are reviewing the bank reversal and will contact you again via email with information on what to do next. You may be asked to provide additional information about this transaction.

Sincerely,
PayPal

今天又來了一封
A payment you received has been reversed. We need more information from you. (Case ID #PP-001
We recently notified you of a bank reversal filed by larry knox for a
transaction on Aug 17, 2010. We need a bit more information from you.

有沒有遇到過類似的朋友，如何應對？
謝謝