Did they give you this address as a deposit adress for your prepaid card? You had to verify the history of transactions before sending your money. The address has two other transactions containing the same amount they asked you to send (about 200$). A deposit address should be a new fresh one, not an already used one.
Also bear in mind not to fully trust an unknown service. How did you came accross this site? Did you dyor before trusting the service with real money? I wish you came here to verify the service before sending btc. It was simple to notice the red flag in the deposit address in addition to suspicious domain.

I am sorry for your loss. Your money gone forever.