Information
iOS devices can natively connect to VPNs that use the L2TP over IPSec, PPTP, or Cisco IPSec protocols. VPN connections can be established over both Wi-Fi and cellular data network connections. It is recommended that VPN connections be disabled when not in use.
Solution
From the MobileIron console, open the Policies and Configs -> Configurations view. Under the VPN Policy verify that all configured VPN connections are authorized.