Lol jackass (the one guy). Maybe this will help... From what i've heard they kinda "nx ban" people they suspect of purchasing nx off a third party site (Large nx transfers for junk via mts), as I've received this error too, and it seems similar to other people that have done the same stuff. Yes i've purchased off of third party sites, and yes i've been "nx banned" (receiving error codes for all modes of charging and also ******s). Submitted a ticket about it and all I got was general "You've been blocked from purchasing nx, please go to a convenience store and purchase nx cards instead" crap.
EDIT: Also in America...