Thank you for reaching out!
Mobile will be shown as not detected, because the serial device is in full control of the modem, and your RUT955 cannot see anything that is happening. It depends on what the modem control is needed for, but for simpler things like sending SMS I'd recommend using "Partial Control". I'd like you to try a few troubleshooting steps:
- If the update was done from legacy RutOS versions (≤v6) (as seen in the screenshot), and the option "Keep settings" was selected, I'd recommend performing a factory reset;
- Try disabling the modem control and see if the device can get an internet connection/register on the network;
Let me know how these steps went, and if the issue persists, please disable the Modem Control, navigate to System → Administration → Troubleshoot and generate a troubleshoot file. It can be attached to the original post and will only be visible to Teltonika moderators.