Hello Marcel
I had to return the remote control, I couldn't connect it to the TV.
Greetings, Brand

I know from experience with older people that it is usually due to pressing a button too long. So press a channel selection button for longer and if that doesn't help, reset the device and reconnect it to the TV.

A very good product for the elderly, so they only have what they need, and there's no chance of them making handling mistakes.