It seems that you are unable to access your University email due to a broken phone that had the Microsoft Authenticator app account for your University. Since you have downloaded the Authenticator app on your new phone, but it requests access from your broken phone, you are unable to receive any codes to approve sign-ins. To resolve this issue, you can contact your University's IT department or help desk to reset your MFA for the affected user. They can guide you through the registration process again and help you set up MFA on your new phone.
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