The Letter of a Complaint

Dear Sir/Madam,

I’m writing you about Freeter “Pro vision” which I bought from your catalog on 21st January for 24, 90 lats. I have added copies of guarantee and receipt.
Your offer price was 24, 90 on 21st January, because you have given me discount 50%. That was inviting and I bought this product, because I needed this product, but yesterday I saw this product in other shop for 19 lats. …