If the contractor fails to immediately inform EGAT of the payment as required under the second paragraph preventing EGAT from remitting the withholding tax to the revenue department within 7 days from the end of the month in which such payment is made, or fails to pay and/or reimburse egat for any amount required under this section within the period of time fixed by EGAT, such period not to be shorter than 15 days from the date of Egat’s notice of payment.