Lenovo — Under warranty laptop keyboard problem

I have a laptop problem with it's keyboard, about 19 days ago I dropped a complain at my nearest service centre ( reference / complain no -[protected]), but problem isn't resolved yet. By the Lenovo's user's manual any type of problem with under warranty products will be resolved in 3 working days, why Lenovo doesn't follow this rule in my case. When I called customer care, they told me " we already sent your keyboard at your service centre", but service centre said, " we have not get any keyboard from Lenovo". Please help me my laptop is 5 months old