Run the main loop also if no wifi is availibe

Official Hardware Nano Family Nano 33 IoT
4

Do you suspect it is blocking here in the loop() if there is no connection ?

I don't know this particular platform, but I guess these callback routines are stubs:

void onNetworkError() {
  Serial.println(">>>> ERROR");
}

and would probably be a good place to set global variables which you can test in the loop() to see if it is safe to start attempting to make a connection to the "cloud".