After updating my iPhone XS Max and iPad Pro 11" to iOS 12.2 Beta 1 i realized my Gmail account in mail was not working. It says "The mail server is not responding" thinking this was a Gmail issue i waited a few hours and tried again and still nothing. So i deleted my Gmail account from my iPhone and tried to readd it well it said it already existed and wouldn't let me. I rebooted and tried again this time i didn't get that error it just wouldn't add it just went back to the add account screen without doing anything. Same issue on my iPad as well. Keep in mind this account works fine in mail on my iPhone XR on 12.1.3 so it is only occurring in 12.2 and only with my Gmail account.