I'm checking the function by uploading the code to the pcb that uploaded the nrf9160 chip.
I checked that the network communication is normal on the previous 9160dk board.
As a result of uploading the code to the custom board and trying again, it has been confirmed that there is a problem with the modem as shown below.
I don't know how to change the uart pin and see if the modem's firmware is the problem.
It would be nice if you could give me some advice.
Thank you.