Accounts being Blocked.

looks like there's some commonalities
gifting with nx prepaid

could it be they're banning people for selling nx finally?

If that's the case, might I inquire about how the mesos were traded? I remember some time ago, this very same thing happened (BillingPP bans) and it was never explained what caused it. Several theories were floated, but a prevalent theme was the transfer of large sums of mesos via 4.999.999 Hired Merchant trades. This was observed even among people (myself included) that were simply doing so as a means of meso transfer or boss loot sale dispersal without any NX involved.