I think you were the victim of a scam since you did not know the reputation of the person you did a favor for. You should not trust someone you do not know or show your face for someone else's debts. Be careful with online friends who appeal to feelings, and as we are good people we help and fall into traps.
Well, I don't really see the the guy in question as a scam because till date he still helps me to sort issues regarding airdrops and all, but I just see him as a greedy person who always want to invest and don't sacrifice for the one he calls a friend. As at yesterday we spoke and he said his friend promised to pay up by next weekend.
But in all, I just the to be so careful....Thanks for adding your voice