This is probably a silly question, but I had a new GivEnergy inverter and battery installed yesterday and the engineers did not ask me for my home WiFi password. The system appears to be sending data in to my GivEnergy account because I can see data about it. But I don't see how it's doing this. Surely it wouldn't come with its own modem?
How is my new inverter connecting to the internet?

7TheAvenue depends on the generation, some with a dongle have a 3g/4g sim card in.
Cdent OK thanks. I guess that is the only logical explanation—unless it is somehow able to piggyback on the connection that our Octopus smart meters already have? (For those I did have to enter the Wifi password) Do you happen to know how I can check the version and whether that has a SIM card?
This is what it says on my dashboard:
Inverter Model
GIV-HY5.0
Software Version
D0.302-A0.302

7TheAvenue this link will show you if it's a SIM or WiFi dongle you have, but these are for Gen 1 inverters only and you said yours was installed yesterday which would lead me to think you'd have a newer inverter
Is the app able to operate in "home" mode ? If the inverter was using 3g/4g, I don't think home mode would work, since that works on the local wifi.
Can you see from your router whether it's connected ? Many routers have a little detachable piece with the details - is it possible the installer just looked at that rather than asking you ?
DD yes, my installer did that. And then gave me a shout when it didn't work. Cuz I'd changed it. 🤣
Incidentally I found the answer in the end. My wife had told the installer the router password! D'oh!
7TheAvenue The Mrs pulled a sneaky on ya 😃