Dear Manager,
I feel sorry to trouble you but I am afraid that I have to make a complaint.
Yesterday I bought an electric fan in your shop, but when I got home and turned it on, it didn't work. So I took it back and talked to the assistant about the problem. To my surprise, instead of helping me solve the problem, the man, in a rude manner, refused to examine it.
Generally, your shop is well-known for good service and that is why I bought the electric fan in your shop. I was really upset to find that such a thing should have occurred in your shop.
I am waiting for a reasonable explanation and expecting an early reply.
Sincerely yours,
Li Hua