Seeking solutions to business English writing

To relevant personnel:

Have a nice day and thank you for reading my letter.

Here's the thing:

A few days ago, I bought a new digital camera in your store. When I got home, I found some scratches on the surface of the camera and the color of the photos taken indoors was not normal. ?

When I went back to the store, I asked the clerk to exchange it for a new one or give me my money back. The salesman ignored me only because I lost the receipt.

I think consumers have the right to protect their own interests. ?

This is the reason why I am writing this letter to you.

I hope you can give me a satisfactory answer.

Waiting for your reply.

Sender: An aggrieved consumer in your store.

I hope it helps you.