Hatte das gleiche Problem gehabt und eine Lösung gefunden und zwar ein "Kaltstart" des Fernsehers, hat sofort beim ersten Mal funktioniert. Nachfolgend die Vorgehensweise habs leider nur auf Englisch was gefunden.
Over time your TV can run low on memory, or a residual electrical charge can build up in your TV. This can result in some funky glitches like an app that stops responding, the menu not opening, or just taking a long time to turn on. Discharging or cold booting your TV drains the charge and resets the main board. If something really weird is happening, try this: with the TV on, press and hold the power button on your Samsung TV remote until the TV turns off and back on. When the TV comes back on, everything should be back to normal.
If you don't have your Samsung remote, there's another way you can discharge your TV. With the TV turned on, unplug it for 30 seconds, and then plug it back in. After you plug it back in and turn it on, your TV should be fine
