If you see a message saying your username already exists, it means another user is already using that exact name. Since usernames must be unique to each account, you cannot choose one that is already taken.
How to fix this: Try making a slight variation to your preferred username. You can:
Add numbers (e.g., YourName2026)
Use underscores or periods (e.g., Your_Name or Your.Name)
Add a short prefix or suffix (e.g., TheRealYourName or YourNameOfficial)
Remember: Your username must still meet the security requirements (at least 8 characters, 1 letter, 1 number, and 1 special character).