Hi, my name is ***** ***** welcome to JustAnswer!
Unfortunately, once your account has been created there is no way to change your screen name. Here's the official statement from Electronic Arts (the owners of Pogo):
Unfortunately, it is not possible to change a Pogo Screen Name after an account has been created. In order to protect users from impersonators or to avoid confusion, once a Screen Name has been set, it cannot be changed.
Sadly, this is a firm policy and the company will not allow you to change your name for any reason. You can, however, create an entirely new account with a different name but I'm afraid that your points will still be associated with your old account.
I really wish I had better news for you. If you have any questions on this, just let me know and I'll be happy to help you in any way that I can.
And please remember to use the rating box to rate the answer at least 3 stars/OK service so that I receive credit for assisting you.