Free new lawnmower but needs minor repair

I have a new Bosch Rotak 32R lawnmower available for free to anyone who is mechanically minded. My husband followed an online hack to lower the cutting blades but it didn't work. Now it won't cut at all although it turns on and makes all the right noises. I'm sure it's probably easy to fix but neither of us are any good at stuff like that and it costs more to get it fixed by someone else than buying a new one. Available from N4