https://support.google.com/voice/gethelp
可以找客服问下啊 回复挺快的，
我问了一下之前那种付 10$转换号码的操作，
换号码前的那个号码是永久的
问：Hello, I would like to confirm if my two GoogleVoice numbers are permanent or for a limited period (I remember I purchased permanent service, but I can't be sure, so I'm asking you)
答：I understand that you want to know if your two Google Voice numbers are permanent or for a limited period. I will be happy to check into this.
Thank you for waiting.
The only number that is made permanent is the number ending with ****.
The $10 is the order to change the number from **** to ****.
问：Can I pay for the permanent service of 4666
答：Apparently, there is no feature to make the number permanent.
It will not be remove unless the number is inactive for three months.
