Why is my remote controlled helicopter helicopter stuffing up?

I have a remote controlled helicopter, it is the Red Arrow 3ch RC model. I flew it and it rarely crashed but one day when i was about to use it, only one wing was working, the other was attempting to start, the lights were fine, the tail was fine. I tried charging it and it still didn't work, I tried changing the batteries and then charging it but still the wing wasn't working, one works and the other doesn't.

I will be willing to buy parts but I don't know which part is missing, please help me, I live in Sydney so if you have a shop where I can have it checked up that would be fine. Thanks!

Stuffed up? Sounds like it's coming down with the flu. Get it to a shop pronto!