Dear @HIaing,
Welcome to the Wefugees Community and thank you for reaching out to us.
It depends what actually happened to you, but you may report the incident to the police in the first place!?
I don't really know a general address where victims of fraud are getting free legal advice. But if you want to share your approximate location with us, I could try to make some research on counselling offices in your area. I also found this website (in English) and (again, depending on your case) maybe the consumers' rights centre (Verbraucherzentrale) can also be a useful contact and they have also local offices.
All the best for you,
Meike