Hello! Seem to have the same issue here, below is output from modemstat ?.
I have also tested the SIM to ensure the issue doesn't lie there.
Outcome: Got modem status OK:
Time: 25 Jan 2018 17:15:56
SIM status: Ready (PIN checking disabled)
Signal strength: -71 dBm
Radio technology: LTE
Signal quality (LTE): RSSI -71 dBm, RSRP -104 dBm, RSRQ -16 dB, SINR -8.0 dB
Radio band: E-UTRA Operating Band 20
Manufacturer: QUALCOMM INCORPORATED
MDN: Not provisioned
Firmware: 17.00.523 1 [July 14 2014 23:00:00] Hardware version: 20004
GPRS Attachment Status: Attached
GPRS Registration: Registered, home network tac:044E ci:0A517316
Preferred system: Auto
Temperature: 41C OK