Subject to subsection (b) of this section, a retail establishment that violates the provisions of this Division is subject to a civil penalty not exceeding $500. (A) The provision of one or more plastic carryout bags at a single point of sale is a single violation. the failure to charge the amount of money required under this Division for the provision of one or more paper or reusable carryout bags at a single point of sale is a single violation. A penalty may not be imposed under this section unless a retail establishment: Is first issued a written notice of violation; and Does not correct the violation within 7 days after receipt of the written notice.