The best players will share the cash prize. So we need to contact each player personally. During the game, we will mainly use email for current exchange. But to be sure that an acouunt is owned by an unique player, we could send an SMS during the login process with a verification code. If the phone number is not entered or incorrect, we couldn't send this SMS and the player's account could be locked. So you'd better enter the phone number and check it is correct.
