Hmmph. It's hard to say, based on your symptoms, what happened, but it wouldn't have been firmware-related.
Just to eliminate the obvious: are any other devices plugged into your POTS line? If so, unplug them all, so that nothing is connected to your POTS service. Now, plug in one known-working analog telephone and call your POTS number. Does the phone ring? If not...time to call the phone company.
If it does ring, then log onto the OBiTALK dashboard and completely delete your 110 off of your account. Within a couple of minutes, you should see the LEDs on your 110 blink as it resets itself. Now, unplug the Ethernet and power cords from the 110, and attach the POTS line to the LINE port, and a phone to the PHONE port. Plug just the power cord back in (not the network cable), and use a paper clip to depress the reset button underneath the unit (look for the small round dimple with a hole in it), to completely factory-reset it. In this condition, with no Ethernet connection and nothing configured, it should still pass through inbound POTS calls. Try it and see. If it fails, then your 110 is defective...its POTS interface might have sustained some sort of power surge.