You can enter the player's information page to bind your game account with your phone number(SMS). 
By clicking your portrait at the left-most corner on the top bar in the game lobby, you can enter into the player's information page.

What's the benefit of binding my SMS?

• You can get a free coins gift after you bind your SMS.

• You can log in your game on any device with your phone number.

• You'll not lose your account since it's bound with your phone number.