How to Write a Complaint Letter About Undelivered Goods after a Purchase ?

Dear_______________,

I am writing to inform you of a delay with my order for __________.

I placed the order at _________ on _________ and was assured that I would receive the order at ______ on __________. This is not the case.

In addition I have received no confirmation of a delay nor any other correspondence. I would appreciate if you could provide me with additional details of this case.

Thank you for your time.

Yours truly,