Why does no map display for any devices on Find my iPhone

I lost one of my iPhones.

Using Find my iPhone, the lost phone displays as Not Connected to Internet.

My other devices also show up on Find my iPhone, and they display a green dot (Connected to internet), however, when I click on any of the devices that DO show they are connected, NO MAP shows up. It's just a big white screen, with green dots.

Why no map???

I need to find my phone!

thank you