@ FMI - There is no way that F Mods can verify what trades did or did not take place as claimed. Nor can we tell if two identical items were sold to two separate players for the same amount. As the trade posted is not being claimed to be on your behalf, but as the poster being party to the trade, there is not F Mods can do about it.
We would need the seller of the item to post here, if they wish to refute the trade as reported.