...
Fuck...

. I have been scammed then! The URL is criptomixer.io and the box says 'Enter CoinMixer code'.
I feel so stupid. It's impossible to retrieve my coins (bar reporting to law enforcement) then, right?
as @bitcoin_arena said, it looks like the site you are visiting is a fake site (criptomixer.io), of the many cases of users who were trapped in fake sites, none of them were able to get their funds back even if you reported to the law enforcement (your chances are small), I am also sorry by your loss.