Inverter Lost connection

My inverter has lost connection, the dongle has no light, the inverter is showing a flashing green and red light!

@Danlambert (GivEnergy) has answered me on Facebook but I've had my wife check it and reboot the router. Now I just need to know what sequence we have to complete to get it back on stream.

Is there a quick way of doing this I am in Austria 😆 and it'll be down to my wife! She is about to send me a video of what it all looks like.

Do I need the engineer app?

If your AC coupled then presumably you just switch off the AC isolator and switch the battery MCB off.
Switch it all back on again and hope for the best with the dongle restarting.