When you are getting the Netflix Error Code UI-800-3 then you should understand that. It is because of the data of the Netflix stored in has a problem with cached data or with the application itself.One of the basic things you can try to resolve the problem is to shut down the device and restart it.The other method for you to resolve the problem of Netflix Error Code UI-800-3 is by signing out the Netflix account and then signing in again.

There are some devices which do not allow you to sign out from Netflix. But you can restart the application of the Netflix which will bring them to the initial state (to the state when you installed it). If you are having the problem even after then you can sign out from the Netflix website.
https://netflixaccountsolutions.com