Does the SIM work in other devices, like a smartphone?
Yes, tested in mobile phone and other GSM router (HUAWEI)....you can see from status printscreen modem is registrated in vodafone
Could it be that SIM is bound to a single device?
No...in other devices working
When performing router's firmware update, did you update with Keep settings enabled?
Have you tried device reset to factory defaults, reconfigure and test it afterwards?
Yes...I tried now after your answer....result is same, disconnected
Might be a stretch, but do you have both mobile antennas attached to the device?
Could you set Service mode in Network -> Mobile -> General to 4G (LTE) only?