While configuring WiNG device, pay attention to way you save the configuration.
There is fundamental difference between commit
and commit save | Commit and Save
command or button
only you have the fail-safe level of applying changes - if the device reboots, the change is not applied
With commit save | Commit and Save
you write the change to startup-config immediately.
This is what happens while using commit
This is what happens once you use commit write | Commit and Save