I have been seeing a lot of Club Penguin Island Geo-Beta players asking why their usernames appear as numbers and not their original username? Well it’s either two of these reasons.
If you have recently Pre-registered your Penguin Username, and logged into Club Penguin Island, your username may still not be approved. Which should only take a max of a few days, so just bare with the current username until the Club Penguin Island Team approves/disapproves of your Username, if they disapprove, they will ask you to select a new Username.
Another reason to why you have Numbers instead of your Username is that you may have skipped the Pick a Username section in the Pre-register, which you can easily solve but fully logging out of your Penguin in the Settings, and re-logging in.
Or it could just be a glitch/bug in the Club Penguin Island game, usually logging out of your Club Penguin Island account and then re-logging in will fix it.
If none of these work for you, then you’ll have to contact Club Penguin Island Support.