unable to login to root

It looks like there might already have been another AWS account created with the email address you are using. If an account was created and closed with this email id more than 90 days ago, the same email id cannot be used to open another account. Please take a look at the below documents

Reopen Account closed within 90 days: https://repost.aws/knowledge-center/reopen-aws-account

Recover password: https://repost.aws/knowledge-center/recover-aws-password

Reference: https://repost.aws/knowledge-center/sign-in-account