Your box does need an internet connection, and you've not mentioned whether this is by Ethernet to your hub or by WiFi.
I can't recall if that internet connection needs to be present during a reboot cycle or if the coax is sufficient.
Sometimes the automated service will attempt remote diagnostics and thereby force you to callback in 10minutes when those fail to resolve... but otherwise you are best off calling faults with this issue.
VM staff respond on here, but it can take several days.
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