I couldn't find the "backoffice form". Can you please specify where exactly can I find it?

At first, I don't know if cryptonex is good or not. I can't give advice to anybody and  I don't have anything on cryptonex. But i also don't see any reason why this should be a scam, like some people seem to -so lightheartedly- believe. If you have any reasons to believe it's a scam, please have some ethics to present us with your research and we'll listen/read your arguements.

From my understanding, this was a promotion move. They randomly selected some addresses to give away a 20% bonus IF they wish to buy CNX. They are not forcing anybody to buy CNX, they didn't give away free money to anyone creating injustice, they just made a promotional move. Anybody can have an opinion if this promotional move was good or not, but that's miles away from something being a scam.

I personally don't have any reasons to advocate for CNX. I don't own a "loose" enough portfolio to invest in any ICO's. But in my view, this promotional move was succesful. I didn't know sh!t about CNX before this and after seing something new in my ETH wallet, I had to research it. So they "made" me research it by offering me a 20% bonus in case I wanted to buy some CNX.

From what I understood, the tokens given are not coins. They are tokens to use IF you buy CNX coins from their "Backoffice". The backoffice is where you open your account to buy CNX from them using BTC or ETH.

If you are given those 1000 CNX tokens, the only way to use them is if you buy CNX coins from their backoffice. You have to transfer the tokens there (i tried to send them from my ETH wallet to the address shown in my Cryptonex backoffice, but they didn't go, they are still in my ETH wallet). If you buy for example 500 CNX coins from their backoffice using BTC or ETH (which you first have to deposit there), then you will get 600 CNX (500+100) and your "1000 CNX tokens" will become 900. Essentially you are using those tokens to get a 20% *Bonus (not "discount" as initially written) at your CNX coin purchases via their backoffice.

I am not 100% certain that I have understood correctly though.

I opened an account at cryptonex backoffice about 15-20 hours ago, applied 2FA on it using an app called "Authy" instead of Google authenticator, logged in a couple of times and 2FA worked fine. Now I am trying to log in to my Cryptonex backoffice account and after correctly entering my password, on 2FA it tells me "Invalid authentication code!". I don't have any funds in there, so I am not worried about losing anything. I just can't access my backoffice wallet anymore. How can I solve this please?

Edit: I checked other 2FA codes in other sites just now and they work fine. So it doesn't look like a problem from my 2FA app.