Netflix not working with nextdns

Netflix on TV and Nvidia Shield does not work when nextdns is set up as DNS server on home router. Error is nw-2-5. Other apps have no issues, eg Amazon video, BBC iPlayer, All 4, etc.

It does work on other clients (eg ios or pc) on same network. Do note Netflix is not disabled on any of my profiles.

Netflix works perfectly with default DNS settings on router.