Sprint: Unable to use phone number for FaceTime or iMessage when using Google Voice
If your Sprint account is integrated with Google Voice, you may be unable to use your phone number to receive FaceTime calls or iMessages.
Integrating your Sprint account with Google Voice may prevent your mobile phone number from being registered for use with FaceTime video calls and iMessage text messages.
This occurs only when your Sprint phone number and Google Voice number are not the same. It should not affect your ability to send or receive SMS or MMS messages, or to receive or place FaceTime calls or iMessages using an email address instead of your phone number.