[Date]

[Addressee]

Dear [Name]:

The shipment of the above referenced merchandise was 
delivered to my receiving department on [date].  While the 
original delivery date was set for [date].  This late delivery 
was approved, in view of the problems that you were 
experiencing at that time. 

Our check for the full amount of the invoice, less our 2% 
discount, was mailed to you on [date].

Enclosed is a copy of the statement received today, which 
includes a charge back for that discount, taken in 
compliance with your terms.  Possibly the source of this 
error lies in the fact that the date on the invoice was not 
changed to reflect the delay in delivery. 

A corrected statement of our account would be greatly 
appreciated. Thank you for your cooperation in this matter. 

Very truly yours,