I had the same issue and it wasnt solved by a firmware update but rather deactivating and reactivating my netflix app on my smart hub.
follow these instruction on the page then at the bottom click on how to activate it.
http://support-us.samsung.com/cyber/popup/iframe/pop_troubleshooting_fr.jsp?idx=428359&modelname=UN55F7050AF&modelcode=UN55F7050AFXZA&session_id=&from_osc=&__ncforminfo=LW6Szg3aYssFkaGPJvklgocKFz8linJpU4DCIbd5t1gEBgrFSF3UxPtlYYfp8HLg_5L5Y-OsLxHoY-9gmjsya_xhGzLnzYGXquyra2itE7H0tkGQ5AqogkEdqQLvbyG2
