PINs can take up to five minutes to arrive. If you’ve waited for a while and still haven’t received your PIN, it may be because GroupMe can’t send PINs to your cell phone carrier or internet phone service (like Google Voice).
To verify your number if you didn't receive a PIN:
Keep the GroupMe app on the PIN screen. If you go through the registration process again, it will generate a new PIN, which could make things confusing.
Contact support and let us know you’re having trouble receiving your PIN. Make sure to include your phone number.
For more help, contact support .