I have OBi200 connected to Google Voice. I couldn't call out, got a bot lady saying the connection was refused by the Service Provider.
Steps to fix that worked in my case:
1. Log in to voice.google.com
with the account tied to OBi, making sure no other log-ins to google are active.
2. If the OBi200 is listed under My Devices, delete it. Registration is no longer needed, just removes that complexity.
2. Make sure your phone number is listed in the upper right. If not, fix that with help from google articles.
3. Make sure you can call out via your voice.google.com
web page using the phone pad in lower right. Do Not Proceed until this is all ok, which shows no fault with Google Voice account.
4. Log in to OBiTalk and click Dashboard. Look at SP1 status in the section below the device information. Mine read: Connect Failed: 403 Forbidden;Token Error. It had a trash can in the next column. Click it to delete SP1, you will re-configure it.
5. Set up the SP1 using video at https://youtu.be/Xw8ZZKxsYPw
. The status in my case did not say connected, it said "Registration is not required" but at least it didn't list a token error. I still couldn't call out, but do this anyway to make sure the software is the latest used.
6. Power down your router, and the OBi200 for a few minutes. Power up the router, then the OBi200.
It all works now. I don't know for sure that steps 4 and 5 are needed. You may be able to fix by ensuring you can call via google voice on their web page, then doing step 6 first. Advice: Don't bother updating firmware before trying this, you might break something. Hope this helps.