Payment Alert Issue

[JokerTM]

I got this message today "The user who paid the MM fee has triggered a payment alert. Please do not continue with the transaction until EpicNPC has replied to this chat. We will try to review this payment as soon as possible, but it can take a few hours depending on the time of day. Sorry for the inconvenience."
What should I do now? buyer have been waiting for serveral hours now.

Transaction #163025

 

[EpicNPC]

Sorry for the delay. The alert will be reviewed shortly and the transaction will then be updated.