Hi,
I've checked the last log you've attached. I believe I see the issue - the operator requires some specific modem configuration before connection and due to that, modem is in "Registration denied" state. If you can, double check if the SIM card can be used on a smartphone or etc. to confirm that the SIM card has the capability to connect. If the issue is confirmed not to be with the SIM card itself, then this was fixed in later firmware versions as far as I know (the one in your device is quite outdated).
You should get the latest firmware I mentioned and update the device, but since I don't work at Teltonika, I can't send you it, you should contact them (or the company you bought it from).
Best regards,