Root account access

I can replicate your issue though I have also used the email/phone method successfully previously. You can raise a support ticket through here - https://support.aws.amazon.com/#/contacts/one-support?formId=contactUs .

Hello there,

I apologize for the inconvenience this has caused you. As you are unable to log in and access the Support Center, you can use this contact form to reach our Support team: go.aws/account-support.

- Rick N.

When the MFA device registered to the AWS root user is lost or deleted, AWS requires identity verification before disabling or resetting MFA. Since you cannot log in to open a support case, use the AWS Account Recovery contact form mentioned in the AWS Sign-In Troubleshooting and Account Recovery documentation. Provide the root account email address, recent billing details, and any other ownership proof requested. After submission, AWS Support will contact you using the verified email or phone number to complete the recovery. If calls are not coming through, confirm that your phone accepts international calls and that the number on file is still active. —Taz