How to change your Activision name: Warzone, Vanguard & Cold War - Charlie INTEL

So I just got warzone, and I need to create an Activision account, as this is the first time it's required. I try to enter in my information, but it says invalid

Call of Duty Warzone 2.0 - How to See Your Activision ID

I'm trying to make an activision account and it keeps saying invalid user. But doesn't ask for a username. Solution? : r/Warzone

My Activision account was hacked

How to Change Your Name In Warzone 2

Keeping your Activision Account Secure

Warzone Mobile Stuck On Logging In To Activision Account Fix - GINX TV

Call of Duty: Modern Warfare Requires an Activision Account For Cross-Play

I can't sign in for a activision account because of user, any fix? (ps4) : r/modernwarfare

How To Create Account in COD Warzone Mobile Activision Account Sign in Cod Warzone Mobile, Sign up