Welcome to the Community and thanks for reaching out about this.
The usernames are designed to identify the users in the app and they can't be changed. However, the users can choose their own display names which will be the ones showing on their profiles instead of their usernames. For more info, you can check this article.
Keep in mind that they can only do that from their own accounts.
Lastly, we don't recommend sharing private info in the Community. In this case, we suggest that you edit your post and delete this info.
If you have any questions, just let us know.
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