I honestly don't know why both commands show two different Network Types, I figured it would have something to do with backwards compatibility or that our carrier doesn't have the strongest connection in the area and it reports the current strength, but the modem itself is definetly LTE-capable.
The second command does always show that the SIM State is valid, which is very confusing to say the least. I had FortiGate 60D with FortiOS 6.0.2 lying around and just tested the Modem with it - the first command still says that the SIM State is invalid (I couldn't test the second command, the CLI couldn't find or autocomplete it though I suspect it would have been a similar result).
Checking a different USB Modem is one thing I didn't try, but unfortunately I don't have one lying around - then again, I honestly don't think it is Modem itself as it does work fine and also connects to the carrier when plugged in into a Windows machine.
By reseating, do you mean plugging the Modem out and back in again or plugging it into a different USB port? Because I have done the former multiple times with vain hope and the latter will be difficult as the FortiGate 40F does only have one USB port.
(After testing the 60D and inserting the Modem back into the 40F, I noticed that the detect command also found a dial-tone (I unfortunately didn't copy it), something it didn't do before, and the query command also didn't show the last lines from my last post. A reboot later and the detect command doesn't show the dial-tone, but the query is the same as before)
FortiGate-40F # diagnose sys modem query
USB status: Connected
IMEI number: 866133022100285
SIM state: Valid
service status: Valid Service
signal level: 2/4
network name: vodafone.de
network type: GSM
location area code:
COMMAND NOT SUPPORT
I hope this helps and thanks again for taking your time, it is very much appreciated!
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