GX400 Won't Factory Reboot

I have a few GX400 modems that won’t factory reboot. I’ve tried in the ACEManager as well as holding the reset button until all the LED’s go Yellow, nothing works.

Hi Mark,

Are certain parts of the device reverting back to factory defaults, but not other (i.e. Cellular Settings)?
If you are resetting the GX400 by using the, “Reset” button, you will only need to hold the button down until all the LEDs turn red. Holding the button down until yellow will set the device into, “recovery” mode. One thing to note: If holding down the, “Reset” until it turns red and the device still does not go back to its factory defaults, you may need to check that the, “Default Configuration Reset” option is not “Disabled”. This option can be found in the AceManager under Admin > Advanced. If this is disabled, the reset button will not be able to reset the device back to factory settings.
If you are performing a factory reset through the AceManager, are you resetting the device with the “Preserve Cellular Authentication Settings”