If someone asks you to transfer U to your wallet, then you can trade through Binance and major exchanges to earn U, and then ask you to download their app, this app is a virus software. After downloading the app, you need to register and upload your avatar. The moment you upload the avatar, all the photos and mnemonics in the album will be read. Then you provide the wallet address to receive the currency. With the wallet address and mnemonics, you can transfer your U away.