Hopefully the web translate got this right...
If the Roku device didn't correctly activate, try doing a hard reset. Find the recessed reset button, and hold it in for more than 30 seconds. This should put you back to the initial first configuration screen again.
Dan
Roku Stick (3600), Ultra (4640), Ultra (4670), Ultra (4800), Premiere (3920), Insignia 720p Roku TV, Sharp 4K Roku TV, Nvidia Shield, Windows 10 Pro x64 running Serviio and Plex on a wired Gigabit network.