Also please remove your email out the post as this is your personnel information and could be open to abuse. Click the gear wheel top right of post and edit
For the game if you have a King account or a facebook account linked to a king account. go to king.com/games and log in and then you will see the settings option and you will have the option to change you nickname in there.
From your other post that is your Fantastic 5 team name, what the team owner has called the team. This is not your name your name seen in the team is ~Polly