I found this out the “hard” way, lol.
When controlling a power station via the App with Bluetooth, I found an issue when owning multiple devices. i.e.
An AC70, AC180 and the Charger 1 were all turned on and being used. The AC70 was App connected, monitoring the charge from the Charger 1. I then closed the AC70, going back to a list of my devices and then selected the Charger 1 to check its data and it would not connect. The error message was “could not find the Charger 1”. I immediately went back to the AC70 and got the same message. I tried closing the App, quickly, and got the same message. By trial and error, I discovered this;
When changing from one device to another, back out of the power station etc. currently being monitored, to your list of devices and wait at least 10 seconds (I wait nearer 30 seconds), then select the next device and all is ok.
It, apparently, takes a little time for the current device to disconnect from Bluetooth, even after closing that device link, before allowing the next device to connect. The App only allows one device at a time, from that App connection. The only way to monitor multiple devices, is to have multiple mobile phones or tablets, with their own Bluetooth connection. i.e. one device per power station.
Hope that helps