Note: The time for the name change you make on platform.openai.com to be reflected in ChatGPT may take up to 15 minutes.
You can change your name in your user settings in platform.openai.com under User Profile Image -> Your Profile -> User -> Name.
https://platform.openai.com/account/user-settings
ChatGPT
Change your name on platform.openai.com and refresh ChatGPT to see the update.
Requirements
Must have some name value
Must be 96 characters or shorter.
Must be only letters, certain punctuation, and spaces. No numbers.