Can not delete my directory

Hello,

I have two directory in my personal azure account. The current on is an old directory and I want to delete it. But when I tried to switch to new directory that I added it asks me to sign in with Microsoft authentication app. There is no definition in my app for this directory so I can not provide code or the notifications are not being sent to my phone. I tried the code of authentication of second directory but it doesn't work as expected. I don't know how to create a Microsoft authentication app definition for this existing directory in my phone.

I need help your help to fix this issue

Regards