I have seen this a lot lately. The only thing to at this point (since you have down the switching off and on) is to do a factory reset. It will bring your Sony apps back to when you bought it and you will have to load the apps again, but from what I can see and researched this is the only way to get Netflix back working on your tv. You should be able go into the apps settings and do a reset.
Just checking to see if you have followed instructions above to correct the Netflix app?