Huge vouch for Arcus, sold him 4b through WU, received payment super fast! (he even took the time to teach an old player like me how to use the grand exchange, much appreciated!)
Rest assured, the issue lies with you needing to check your email or your paypal address, and make sure that you do not need to accept the payment by any means.
The payment was sent from my Chinese helper, and I told him to send the payment then left the computer, which is why I suddenly went away. He sent you the payment, I'm sure the email is not fake.
If for some reason there is a problem, please contact me while I'm online and I'll help you fix it .
With that said, 6b or so bought so far today as I've been out, but could still use some more now!