电话版(口头,非正式):
Excuse me. I'm sorry to trouble you. We've sent a request to you before, but we haven't received any refundment yet. Thank you!
电邮版(书面,较正式):
Dear XXX,
We're sorry to inform you that we haven't received any refundment yet, for we have sent you a request before.Thanks!
Best regards,
xxx
I'm sorry to trouble you ,I sent the request, but I haven't received the refundment.
Excuse me. I have sent an request before but no refund has been received yet. Thanks!
Excuse me. I have sent a request but I haven't received the refund yet. Thank you.