Response to Improper Billing After Payment
On [12-10-2012] I received your letter which indicated that I had a balance owing in the amount of $. On [date] I mailed a check to you in the amount of $[dollar amount]. You should have received my check prior to writing your letter and I am, therefore, somewhat concerned.
If you have not received my check by the time this letter arrives, I would appreciate hearing from you so that I may issue a stop payment on the funds. I am waiting anxiously to hear from you to get this matter quickly resolved.