Back up a Microsoft Authenticator work account and a Microsoft Authenticator Personal Account

Question

I have Microsoft Authenticator on my personal phone and on my business phone. My business phone has bmy business Microsoft account. I need to replace my existing business phone with a new phone. I find that you must back up the business Authenticator account to a personal account. However, my personal account has a backup of my personal authenticator. How can I back up my business Authenticator to move to a new phone?