There are several sites that the admin of the site pump some particular coins like solana,btc and XRP and many more for them to attract those who do crypto arbitrage to deposit their money.After you perform some trades and they see you have put so much money on the site they will block your account and demand for another huge money for wallet verification.Because they have see some fraud transactions on your account.So be carefully ,some of the site are Lexidex.com,Teedex.com and qepweb.com am a victim for these sites