(a) Vendor entitlements. A vendor shall be entitled to an additional penalty payment when the vendor is owed a late payment interest penalty by an agency of $1.00 or more, if it:

1. (1) Receives a payment dated after the payment due date which does not include the interest penalty also due to the vendor;
2. (2) Is not paid the interest penalty by the agency within 10 days after the actual payment date; and

3. (3) Makes a written request that the agency pay such an additional penalty. Such request must be postmarked, received by facsimile, or by electronic mail, by the 40th day after payment was made. If there is no postmark or if it is illegible, the request will be valid if it is received and annotated with the date of receipt by the agency by the 40th day. The written request must include the following:

   1. (i) Specific assertion that late payment interest is due for a specific invoice, and request payment of all overdue late payment interest penalty and such additional penalty as may be required; and
   2. (ii) A copy of the invoice on which late payment interest was due but not paid and a statement that the principal has been received, and the date of receipt of the principle.