Inverter Offline

I want to change my Timed Charge and Export settings, but keep getting the message 'Inverter Offlne. Please try again'. I've been trying for over an hour.
I've tried 'Restart Inverter', but that comes up as 'Restart Failed'
Any advice or suggestions?

Have you established whether the inverter is actually off-line or that your app just can't see it?

Okay now!!! Inverter has just started to allow changes.