NOTIFY CUSTOMER THAT CREDIT LIMIT HAS BEEN EXCEEDED
As you know, we are happy to accommodate you with credit terms to better facilitate doing business together.
Unfortunately, our records indicate that your $[CREDIT LIMIT] credit limit has been exceeded. Since we know you to be a valued and conscientious customer, however, your purchase (P.O. #[PURCHASE ORDER]) was approved nonetheless. I urge to you check your records to determine whether our records are incorrect.
If you determine that our records are correct, I request that you forward to us payment in the amount of $[DIFFERENCE], to bring your account up to date. I apologize for any inconvenience this may have caused.