It’s been more than a month since I ordered (what?) from your companyand the item has not arrived. Did you actually shipp the item? If not I want to have a refund.
This is what you should write:
I ordered (what?) from your company more than one month ago, and have not yet received my order. (Provide the order #) Please let me know when it was shipped, and send me the tracking information. If you have not yet shipped the item, please cancel the order and refund my money.
Do not use "hi" (and do not use an exclamation point!!) in a formal email or letter.