Sorry to hear about this difficult fault, I will admit I don't out rightly know the fault but I'd like to investigate further.
So previously when this was working fine, had you had to set-up port forwarding rules? If so, are these still in place? It might be worth factory resetting your Superhub and then restoring it from a back up and see if that helps.
I'll also leave this post open for other members of the community to add their advice.
Thanks again for posting,
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