When email fails to sync across devices, it’s typically due to account configuration, connectivity, or outdated apps. First, ensure you’re using the correct sync settings—most email providers have specific instructions for setting up accounts on different devices. Make sure both devices have a stable internet connection, as poor connectivity can interrupt sync. Updating the email app or operating system often resolves compatibility issues. If your email account has a limit on the number of connected devices, try removing and re-adding your account. These steps generally restore proper syncing across all your devices.