If you get "Out of area" followed by your GV number, it is probably a GV setting issue.
Also double-check your Call History (in the Obi200 web UI), if you see all incoming calls like
"From GT1(*your GV number*)", it means GV is sending your GV number instead of the actual caller phone number to Obi200.
Solution:
Login to Google and open GV (
https://www.google.com/voice/b/0#callsettings)
If you are on the new interface, select "Legacy", then open Settings, choose Calls.
For "Caller ID (incoming)" select the first option "Display caller's number" instead of the second "Display my GV number".
Since GV does not provide ID names, you'll still get "Out of area" on top, but below you'll see the real caller's phone number.