How can I send money using the phone number if I have BT Pay and live in Italy?

You can send euros or lei, based on the phone number, from BT Pay.  

Euro: If the person you want to send money to has BT Pay, you just have to choose the option Trasferimento, respectively Send Eur and you choose the person to whom you want to send money from your phonebook. You enter the amount of money you want to send and the transaction details, you authorize the transaction by entering the PIN code or through biometrics.  

Lei: Access Send RON – if you do not have an account in lei, you will be directed to open an account in lei. You can fund it by currency exchange from the euro card, you choose the person from the agenda to whom you want to send the money, enter the amount and authorize the transaction by entering the PIN code or through biometrics.