Supported flag.
Small question for OP - did you send them screenshot that you are holding 0.5BTC in your wallet, because rules are:
Hello everyone, 1 BTC giveaway happening right now from one of the biggest crypto companies to first 3 people!
Requirements:
1) You should have at least Member Account
2) You should have at least 0.5 BTC in your BTC wallet
All you need to do is contact us by Telegram @btcexchangegiveaway as quickly as possible with the screenshots proof.
I believe if you did you can create red flag.
If you didn't they can also say that you have tried to scam them which resulted in damage (damage can also be mental) and place red flag on you:
This user violated a casual or implied agreement with me, resulting in damages.
This might sound like CH's point, but law and justice are not the same thing and you can unintentionally fuck up and get red flag while exposing scammers