Found what I believe is a BUG in mini-graph card. I'm running latest version of HAOS and mini-graph-card module.
Problem: graphs never display (constant spinning circle) on dashboards ONLY when HA Companion App (running on 4 different iPads) has Wi-Fi- disabled (using Ethernet via USB-C) or when HA Companion App Location Services set to Never.
Problem goes away and graphs work correctly as soon as I enable HA App location service and Wi-Fi. Problem easily repeatable by just disabling Wi-Fi. I have 4 iPads that have been running HA Companion App just fine with mini-graph-card for many months but I was always using Wi-fi. I just switched some of my iPads to Ethernet (via usb-c port), with Wi-fi disabled and problem with mini-graphic displaying has started. Mini-graph cards display fine on same iPads using web browser--just not via HA Companion app when wi-fi is disabled.
Why would mini-graph card even care about wi-fi being enabled on the HA Companion App?