Do a bit more troubleshooting.
For incoming calls what does the 202's Call History show as the destination? The "To" in the right hand column? It should be "ph" or "ph1" or acceptable variation. If not, why not and what is it showing?
If it showing the destination as the phone port that has a phone plugged in, observe while an incoming call is being made. Does the appropriate Phone LED on the OBi202 blink? If yes but the phone is not ringing suspect the phone. Ringer turned off? Ringer faulty? Try another phone.