Is it a scam, they told me they are from bitcoin mining company and they are professional in their job so they are helping us to get more bitcoins.
if they can help you get a lot bitcoin with minimum effort on your part, why would they need you?
you fell to an obvious scam, you should be cautious with the very high return... it's a big hint
So how can we trust this bitcoins investment. Is there any trusted agency or applications so we can invest there.
Nowadays in FB many people post that for 100 $ you can 1000 $ just by investing no legit like that, why cant bitcoin company block them.
by using your head, clear thinking, some logic and DYOR
(do your own research) before investing
it's your own foolishness to think that by investing $100 you can get back $1000
there is no "bitcoin company" that can block them, bitcoin is a peer-to-peer currency