There are a few ways to regain access to your Stripe account if you no longer have your authorised two-step authentication device (for example, your mobile phone) and/or backup code.
If you are the account owner, submit a request through the account recovery form. For security purposes, you will be asked to provide detailed information about your account OR upload a government-issued form of ID to confirm your identity. Once we've confirmed your identity, you'll be able to sign in using your password.
If you are NOT the account owner, the primary account owner or an account administrator can help solve this issue for you. One of these individuals will want to simply reset your two-step authentication from the Stripe account in the Team settings page. This will send an email to you with a link to regain access to your account.