The verification test message test pattern did not display on the status indicator and you did not receive a response.

This means the device can neither receive nor transmit test messages. The SMS Lite must be running a recent version of the firmware to process the test message. If the device was purchased prior to June 2019 then try programming the master phone number then sending the info command. If that responds then the SMS Lite is receiving and sending SMS messages. Stand near the device and check that you have reasonable network coverage (a few bars) on a mobile phone. Check all connections to the antenna are firm and that the antenna is in an open area away from or not enclosed in metal objects. Avoid long antenna cables (over 5m) and ensure low-loss coaxial cable is being used. If you are unsure about cellular coverage or antenna performance in rural areas, try setting up the SMS Lite in a location with known good cell coverage and check operations.