@tom Curriously, it does not seem to accept -p 0000, which was our pin. We changed it to 1234, which is accepted, but that didn't help with the issue, and it acted identically to providing the wrong pin.
quectel-CM -p 0000
[03-02_13:02:16:064] Quectel_QConnectManager_Linux_V1.6.0.24
[03-02_13:02:16:064] unknow -p '0000'
quectel-CM -p 1234
[03-02_13:02:39:300] Quectel_QConnectManager_Linux_V1.6.0.24
[03-02_13:02:39:305] Find /sys/bus/usb/devices/2-1.1 idVendor=0x2c7c idProduct=0x800, bus=0x002, dev=0x003
[03-02_13:02:39:307] Auto find qmichannel = /dev/cdc-wdm0
[03-02_13:02:39:307] Auto find usbnet_adapter = wwan0
[03-02_13:02:39:307] netcard driver = qmi_wwan, driver version = 22-Aug-2005
[03-02_13:02:39:308] Modem works in QMI mode
[03-02_13:02:39:325] cdc_wdm_fd = 7
[03-02_13:02:39:399] Get clientWDS = 15
[03-02_13:02:39:430] Get clientDMS = 1
[03-02_13:02:39:462] Get clientNAS = 4
[03-02_13:02:39:494] Get clientUIM = 1
[03-02_13:02:39:526] Get clientWDA = 1
[03-02_13:02:39:557] requestBaseBandVersion RM502QAEAAR11A04M4G
[03-02_13:02:39:686] requestGetSIMStatus SIMStatus: SIM_PIN
[03-02_13:02:39:718] requestGetProfile[1] 3gnet/carl/1234/1
[03-02_13:02:39:749] requestRegistrationState2 MCC: 238, MNC: 20, PS: Detached, DataCap: UNKNOW
[03-02_13:02:39:781] requestQueryDataCall IPv4ConnectionStatus: DISCONNECTED
[03-02_13:02:39:781] ifconfig wwan0 0.0.0.0
[03-02_13:02:39:803] ifconfig wwan0 down