Did you try setting the DNS to Google DNS?
It's 8.8.8.8 and 8.8.4.4
I can't guess why this happens but the conspiracy theory is out there if you read more.
If you are trying to get US Netflix in Canada, then we know that no one supported that.
Bob
Am I the only one with this issue? I have an LG LA6900 and Netflix won't work anymore with a US dns in the wifi settings. Tried resetting the app. Logging out. Sometimes I can browse the titles but cannot play anything.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic