Before creating a new account, try to determine whether your original Microsoft account still exists. A new account will not restore Xbox purchases, achievements, game progress, or licenses tied to the original account.
A few questions:
- Can you sign in at https://account.microsoft.com in a web browser?
- Does the password reset page recognize your email, or does it also say "This account doesn't exist"?
- Is your Microsoft account an Outlook/Hotmail/Live address or a Gmail/Yahoo address?
- Did this start suddenly, or do you suspect the account may have been compromised?
- Does the blank sign-in screen occur everywhere (Xbox app, Microsoft Store, browser), or only in specific apps?
Feel free to update here if anything comes up!