Information
This control defines the number of minutes the device can be inactive before requiring the password be reentered. By default, if a passcode is defined, an iOS device will automatically lock after two minutes of inactivity, and the default Exchange ActiveSync policy setting applied for users not assigned to a mailbox policy sets an inactivity lock at 15 minutes. The recommended setting is 2 minutes or less.
Solution
From the MobileIron console, open the Policies and Configs -> Policies view. Under the Security Policy verify that Maximum Inactivity Timeout is set to 2 or less.