Microsoft Authenticator not working, after getting a new phone

I've been using MIcrosoft Authenticator for a couple years. Yesterday I purchased a new Samsung phone, I performed the Smart Switch to move everything off my old Samsung phone to my new Samsung phone. I just tried accessing a resource (my work MS Teams account), which requires me to authenticate using MS Authenticator. It said that I was supposed to go to MS Authenticator, to authenticate my login to my work MS Teams.

Only, there was nothing in Authenticator. Nothing for me to approve. Nothing.

So, what's wrong? How do I fix this? This is a showstopper, so it's got to be fixed TODAY!