A unit is not liable under § 15-104 of this subtitle for interest:
(1) unless within 30 days after the date on the State’s check for the amount on which the interest accrued, the contractor submits an invoice for the interest;
(2) if a contract claim has been filed under Subtitle 2 of this title;
(3) accruing more than 1 year after the 31st day after the unit receives an invoice; or
(4) on an amount that represents unpaid interest.