How do I disable 2 step authentication

Recent purchase - set up accout with 2 step authentication.\ issue is whenever I try to log in with my phone. As soon as I move focus on my phone to get the SMS. it logs me out the app... And so on.... quite infuriating really. And when I finally get into the app. there is no device pair availabe at all. surely this should be more simple than this. Previous (different make of doorbell). 4 clicks and done