Flippy same issue with TCL Flip 2. Location setting is turned on. Closed Waze, reboot phone, restarted Waze, still say no GPS signal. I am outside for several minutes with clear skies.
You do not need service SIM to have waze work. it might help getting a GPS fix faster, but GPS is a separate module that works even without a SIM card in phone. Wifi is on and have internet access, b/c I can search for where to go in Waze.