If you are looking for the for the Galaxy S6 Edge (SM-G925F), you are likely facing one of two scenarios: you are trying to fix a "No Service" or "Unknown Baseband" issue, or you are troubleshooting a null IMEI.
After an IMEI repair or patch certificate process, the network may fail to register. Flashing a compatible modem can restore the signal. g925f modem file u6