No more than 1 alcoholic beverage may be sold to a person less than 15 minutes prior to closing each day that a license is open pursuant to this title. Any server who violates this section shall be guilty of a violation, and shall be fined $100 for a first offense, and $250 for a second or subsequent offense accruing within 1 year and shall be further required to take a course of instruction pursuant to Chapter 12 of this title (Delaware Responsible Alcoholic Beverage Server Training Program) within 90 days.