英文投诉信怎么写啊。。。

要投诉的公司
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Dear Sir/Madam,
I have been a pleased customer with your ABC Friendly Mart over the years. On my most recent visit, 事发日期+时间, I received poor service that I felt I should bring to your attention.
I was in the store to purchase some clothes. When I got into the checkout lane, the cashier, who was wearing a nametag that read "Jane" told me that I would have to wait for a few minutes until her freshly painted fingernails had dried before she could ring me up. She was also on the phone talking to a friend during this time. After ten minutes she got off the phone and proceeded to ring me up. Imagine my surprise when my bag of chips and small drink totaled $7.98. I told her that I thought there must be some sort of error. She proceeded to tell me that she didn’t set the prices and that if I didn’t like the prices that I should shop elsewhere. Needless to say, I went across the street to the XYZ Quick Shop for my purchase. (这段主要是投诉哪个售货小姐，最好有名字，然后大概是怎样的情形。Lz自己改改。)
I was extremely disappointed with the service I received that day. If you would please address this issue with your cashiers, I would greatly appreciate it. I enjoy shopping at your store, however if I receive this type of treatment again, I will take my business elsewhere.
Thank you for your cooperation in this matter.
Sincerely,
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