Problem solved
Just purchased a Yuka Mini. It worked fine for 2 weeks. Now it stopped working and the so-called chat-support sucks! No reply and its the same autogenerated answers in their chat. They refuse to take the mower back - and there is no solution to why it stopped working. UPDATE: Chat support is not a success. So after I called them and talked them I did manage to get a new Yuka Mini nsent to my address. Its now 3 stars and I recommend the mover - just skip their chat and call them if you have any problems.