Hey @luddite,
We'll do our best to help. In my experience Nokias can display this for any issue where an Internet connection isn't available, so unfortunately it doesn't point us to a specific issue. Check our Network Status checker to see if there's any work going on in the area, just in case it's the network rather than your settings.
I'd also try switching mobile data off and back on from the settings, and if you've got an option to "reset APN settings" this may help too.
Let me know if any of this helps!
JonathanB
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