Notwithstanding any contrary provision of this chapter, the tax imposed by this article shall be due and payable on the first day of each calendar month next succeeding the month during which the room was occupied. All taxes not paid by the twenty-fifth day of the month in which they are due and payable shall be deemed to be delinquent. The operator shall be assessed a penalty of ten percent (10%) on all delinquent amounts as well as interest of one percent (1%) per month or fraction thereof from the first of the month in which such tax becomes due and payable until the date of payment.