EM7511 Switches From "Turned Off" to "No Service"

I manage a fleet of tablets that all have EM7511 WWAN cards in them and every so often one of the users approaches me with their equipment saying the cellular connectivity is no longer functional. Besides the issues we’ve had with these not reconnecting to a network after losing service we also have an issue with these where they won’t connect at all after restarting or really just doing anything with the tablet. I’ve tried drivers and firmware, of course. Skylight says that the wireless switch is off which of course is interesting because there is no wireless switch. I can issue AT commands to the modem and I’ve tried AT!RESET but then the status of the connection changes from “Turned Off” to “No Service”. I poked around a bit in the AT commands some more and it says that the modem is in “Low Power Mode” which may be something of interest. I’ve tried issuing AT!PCINFO? and it returns an error even after entering the password. I’m sure I can’t be the only person experiencing this issue and any assistance is appreciated.

When you have a modem in this state, what is AT!GSTATUS?, AT!PCINFO?, AT!IMPREF?

AT!GSTATUS? output:

Current time: 222
Reset counter: 2
Temperature: 40

AT!PCINFO? output:

State: Low Power Mode
LPM voters - Temp:0, Volt:0, User:0, W_DISABLE:1, IMSWITCH:0. BIOS:0. LWM2M:0. OLPM persistence - None

AT!IMPREF? output:

preferred fw version:
preferred carrier name: VERIZON
preferred config name: VERIZON_002.039_002
preferred subpri index: 000
current fw version:
current carrier name: VERIZON
current config name: VERIZON_002.039_002
current subpri index: 000

This is a different system with the same WWAN card the EM7511 but the firmware was outdated. It won’t let me update the firmware. A lot of these systems we have do the same thing, however. The firmware updater gives me the following errors:

Primary error code: 12 - No download port available
Secondary error code: 68 - Received incorrect response
Device error code: 0x0 - Unknown device error code