It was an obvious scam from the start.
What is too good to be true, is probably ain't true.

You don't expect to get 20 euros worth of bitcoins for doing nothing, there's just no one who will give you that, no matter what.

I don't even think that someone is stupid enough to fall for this, but for the next time, you should google the site before using it, so you can make sure you aren't wasting your time for nothing.