This is pure speculation but it may have something to do with the data dongle. I know you can't communicate with the inverter with a wired serial connection for data collection when you have the dongle installed so maybe an dongle firmware update has caused a comms fault. I have some equipment to test serial data transmission but I haven't had time to look at it again. I have opened a support ticket so hope to hear something.
This is pure speculation but it may have something to do with the data dongle. I know you can't communicate with the inverter with a wired serial connection for data collection when you have the dongle installed so maybe an dongle firmware update has caused a comms fault. I have some equipment to test serial data transmission but I haven't had time to look at it again. I have opened a support ticket so hope to hear something.