iOS mobile app 2FA - When login is required, 2FA field goes away in app during multitasking

In iOS, in the mobile app, the 2FA screen (where it says to put in the code they just emailed you), goes away upon multitasking to retrieve the code, forcing you to close the app and log back in, at which time they email you another code, ad infinitum.  If I had been in the field this would have been a real problem for me.  

While we're talking about the behavior of the mobile app, the disconnection of sessions during iOS multitasking is also terrible.  I don't think it was this way in Android, but it's been a while and this may have changed.