copied from google.com/voice when you tell it to deactivate gv voicemail on sprint.
Note: Sprint will enable free conditional call forwarding for busy calls or calls not answered on your mobile phone beginning in mid-November. Until that is completed, this feature may not work or you may be charged every time someone leaves a voicemail.
Learn more
Follow these steps to deactivate Google Voice on your mobile phone.
Enter the following exactly as written, as if you are dialing someone:
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