But my online handler in all social networks is just dominguezdaniel without the number 1.
I see that username https://vercel.com/dominguezdaniel is 404, so I was wondering if I can claim that username and if you can change it so the number 1 in my handler can be removed.
It looks like you already have an account with that username – it’s not connected to your github and uses an email login with a custom domain (it’s the one starting with S).
If you log in and delete that account, it will free up the username so then you can go to your main account and change the username yourself in settings
If that doesn’t work or you can’t get access, you’ll need to make a case at vercel.com/help where the support folks have more power to move account information