Why is my SolaX Pocket WiFi dongle flashing red?

Short answer

On the Pocket WiFi V4, a flashing red light means the dongle can't talk to the inverter. A steady red light means it can't join your router. Alternating red and green means it can't reach SolaX Cloud. Your panels keep generating either way. Pressing the button twice restarts the dongle, and holding it for over 5 seconds factory-resets it.