Hi. We can't log in. I think because the name I used to sign up was an older one. Can I change to the new one?
Is it the same account with a name change or is it a brand new, different account? If it's a new account, you would have to fill out the whitelist application for the new account. If it is just a name change, it should work automatically.
KittyCat225, What message are you receiving when you attempt to log on? We show no record that the name associated with this account has had any prior names. Are you certain your minecraft pc account is KittyCat225? Additionally, what version of minecraft are you running when you attempt to log on? You should use 1.12.1. You won't be able to log on with 1.12.2 or "latest version".
If you have recently changed your name, you might have to re-login to the minecraft launcher itself. I have to do that for my character.