Look at the letter below. Rewrite it as an individual letter to a customer - which would certainly be necessary if the customer had ordered ten items at this price and not just one.
The first lines are done for you below.

Dear Customer:

We regret that your order is being returned to you due to the reason(s) checked below. Unfortunately, prices of equipment are constantly changing and these changes are often not reflected in our advertising due to the months between preparing advertising copy and its publication.

Shipping and handling are also variable, so please include the proper charges if that is the reason that your order cannot be processed. It is always best to call us when more than one item is requested, to obtain exact shipping costs for your order.

From time to time items are discontinued and, though this is beyond our control, we will be happy to suggest products which are suitable. Please give us a call on our inquiry line (304) 739-8723.

Thank you for your patience, and we hope to serve you when the problem with your order noted below is corrected.

(_) Item requested is no longer available.
(_) Item requested is not yet available
(_) Invalid credit card number. Please check your card.
(_) Insufficient postage and/or handling. Please add $____ for shipping.
(*) Price change. The new price is $ 145.75
(_) Other:_________________________________

Additional notes: The product has been upgraded - the new version performs better than the original version, which has been discontinued.

Begin your letter like this:

12 April 19--

Dear Mr Stafford,

Your order #767 999 for ten CX 99 processors

I am sorry to inform you that we have been unable to process this order and I am returning it to you for your attention.