Hello.
We have a hybrid environment with Office 365 and Exchange 2013. My mailbox used to settle on Office 365 cloud space, and I always use Outlook Android version to connect my mailbox. Yesterday, I move my mailbox back to on-premise space, then I cannot connect mailbox with Outlook Android forever. Every time I tried to connect with Outlook Android, it redirected me to Office 365 login page. I tried to uninstall Outlook Android and install again, but it was not work. The problem was just happened with Outlook Android, other clients (ie. BlueMail (Android), Outlook (Windows 10), or Android native mail) work perfectly.
I can connect to mailbox by ActiveSync with all clients, but Outlook Android. Did I lost something important?