How can I get a google voice number outside the US?

I'm trying to get a google voice number but for some reason I can't.

I created a google account using a usa proxy, went to voice.google.com, managed to confirm using a textplus number but the number I chose doesn't get added to the account!

I get this message after confirming the number: "Phone number added (XXX) XXX-XXXX has been successfully linked to your account and will ring when someone calls your Google Voice number."

And I see this: http://prntscr.com/j2cjrv

But why…

How can I get a google voice number outside the US?