Don't worry much about an untrusted feedback. That guy is a troll. Anybody who visits your trust page can have a positive impression after looking at your other trusts feedback. That non DT trust is not even reflecting in your trust rating.
looks like that son of a bitch, just left you negatives as well, there is no way to ban him?
even if it is fake, it still bothers the hell out of me
EDIT:
I found this on google:
https://imgur.com/gallery/xaz3kseems to be a well known scammer, his Skype Peter.maloa, links him to a lot of shit