Hello Ashley Power,
Thank you for reaching out to the Microsoft community!
Based on the information you have shared with us; I understand that you have a concern regarding Microsoft Authenticator for authentication for the app. As this issue is more related to the Microsoft t Authenticator, I would recommend post this query in our dedicated community for Microsoft Authenticator - Microsoft Q&A. You will be able to find specialized experts in this matter that can provide unique solution to this issue.
You can use the following link to post the query in Microsoft Authenticator - Microsoft Q&A
You can also check the Microsoft Authenticator FAQs Microsoft to see solutions for most frequently asked questions on Microsoft Authenticator FAQs - Microsoft Support
I apologize for redirecting you to a different community. I believe this step will ensure faster and more accurate assistance for your specific scenario.
I appreciate your patience and understanding. Have a great day!