Netflix says 'This device is not optimized for Netflix. (5001)'

If you see an error on that says

It means that the device you are using has not been certified by Netflix, so you may experience problems watching. For the best Netflix experience, we recommend using an alternate device. You can also select Ok to close the error message and attempt to stream on your current device, but Netflix cannot guarantee that you will experience the intended video or audio quality or that all features will be present and working properly.