Several users have reported that their devices (iPads or iPhones) are stuck or frozen; while an alert message saying “iCloud Backup. This iPad (or iPhone) hasn’t been back up in two weeks. Backups happen when this iPhone (or iPad) is plugged in, locked and connected to Wi-Fi.” Users have also reported that simply pressing the home button does not work.
Please note that this is a status message advising you that your device has not completed a backup in a specified number of weeks. If this message will not go away, please press and hold the Sleep/Wake and the Home button (together) for about 10 seconds until you see the Apple logo.