I have got same thing a while ago by mentioned fake @ngc, I believe that many whales account has been used for such scamming. Thank for letting us know @gavvet, very much appreciate.
And this is the last comment by @themarkymark on my post regarding scamming things;
If someone messages you on Discord or Steem.chat out of nowhere selling steem power or upvotes, 99.9999% chance it is a scam. Even more so if it is much better than the typical market prices.