Unfortunately no clues, but I encounter the same issue.
I found that disabling/enabling the dhcp-package or restarting the router can solve it (temporarily)

Hi Normis,

My provider is Vodafone in the Netherlands. They haven't yet given any documentation as far as I am aware.

The only thing I found is that they use a solution from Ericsson: https://www.ericsson.com/news/1993653.

Hope that will give someone a clue.

Regards,

David

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