Google Voice network rule?


I would like to be able to allow google voice calls on an android phone, so that my kid can text with friends from school without having to buy a SIM card.

If I put it in parental mode I can both make and receive calls without any issue. However, once I turn on any filtering at all (even the “Low” mode with everything I could find in categories turned on) they are able to place calls but not receive them. Calls to the Google Voice number still don’t ring unless I put it back in parent mode.

Does anyone have any idea what site(s) I need to whitelist?