There seems to be some bug in the newest Cisco 5G cellular gateway (CG522-E), shipped with 17.05 firmware. When you insert a SIM card, Linux cwand subsystem crashes and it keeps cycling, not detecting the SIM card:

Subsystem stopped: cwand
CellularGateway# pid 4342's current affinity list: 0-3
pid 4342's new affinity list: 0
pid 4344's current affinity list: 0-3
pid 4344's new affinity list: 0
pid 4345's current affinity list: 0-3
pid 4345's new affinity list: 0
pid 4346's current affinity list: 0-3
pid 4346's new affinity list: 0
pid 4348's current affinity list: 0-3
pid 4348's new affinity list: 0
pid 4349's current affinity list: 0-3
pid 4349's new affinity list: 0

System message at 2022-07-28 07:35:27...
Subsystem started: cwand

Guessing this has something to do with congestion windows parameter settings in the Linux subsystem, in combination with our SIM card (mobile network) specifications.

The only solution was to downgrade to 17.04 firmware. That fixed the issue for now.