NPL Products - Less 30% Offer Was Ended Early

The NPL less 30% off all products was supposed to have ended on the 30 November. Just after 11pm on the 30 November 2022 the prices reverted and the discount was no longer applicable. I have written 2 emails without a response back. I have also tried calling the customer care line but end up holding for too long. This is not a fair practice as the special was for in store and online - one should have still been allowed to order irrespective of the time as long as it fell within the timing.