I have read how many have been doing a whole system restore in order to get rid of this annoying icon. I found the solution.
Go to settings< then .. "call"< then ... clear notification.
Hope this helps. It did mine. I had it on forever and found this by snooping around. I tried so many other things that never worked. Uninstalling and re. Installing Google voice .. to many other things.. but one thing I would never do was reset my phone. He** to the no. Lol.
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