How do I restart or reset the game?

How do I restart or reset the game The Island Castaway?

start a new profile and delete your old one

How do you do that ? I'm on android phone

At the beginning of the game, it says "Welcome XXXXX (username) If not XXXXX click here. You Click here and then add a new player. Then the game starts over from where you left off. Or you can delete your username and it will prompt you for another.