4G Dongle offline

I have a 4G dongle as my system is in a barn, so too far for the wifi to reach. It is showing as Offline and has been for weeks now as despite my trying I have failed to get any help from GivEnergy. I've tried following the video advice on how to reset by pushing the small button for 15 seconds but nothing changes and it continues to slowly flash blue. I've tried 3 times now, waiting for 20 mins between. My query is that everything I see on fixing this refers to WiFi - for example "look on your phone for the Wifi connections of the dongle, it's name starts with a W"
Is all the supposed advice they give the same for my 4G version is the question I guess. And am I supposed to stand by the inverter with my phone and see the dongle name under available WiFi,'s?
I'm sorry, I'm not very technical, but hopefully somebody might understand 🤞😀

I dont think anyone from GivEnergy reads this forum. It might be better to post here.
The Dragon helped me in 2 hours of posting

https://community-beta.givenergy.cloud/

Breconbuff it may be that the data service on the 4G dongle has run out. Somebody else had a similar query recently and it was unclear how long the data service was paid for.

You could try putting the SIM card from your phone into the 4G dongle and see if that works. If it does, then just go and buy a data only SIM. Lebara are quite cheap, you don't need a lot of data