In order to Upgrade/ Downgrade Type, You Have you must first log into your TGS player profile Click Here
Dashboard: On the right-hand side under TGS Rank you will see a button Account Type.
Click Account Type: A menu will populate with your account information.
Current Account Type: Here you will see the account type you currently have. The three account types are Teen Free, Teen Plus, Teen Premium.
Select An Option To Upgrade: Here you will see options for the three types of accounts and the upgrade cost for each. To upgrade, simply click the option you would like to upgrade to. Follow the prompts to add your payment option.
Select An Option To Downgrade: Simply click the option you would like to downgrade to.