I had the same issue. I solved this issue by purchasing a WIFI extender. My WIFI and TV are on opposite ends of the house. My cable provider said that the WIFI signal was not strong enough for a reliable connection. Once I set up the WIFI extender, I have had zero issues!!!
It’s not the router as I have said before the engineer I had out to my tv said Samsung are aware of an issue but won’t admit it !
The engineer needs to replace my board and WiFi unit so that it won’t drop the WiFi.
Get your act together Samsung!
First and last Samsung tv I will buy.