Rewards points all of a sudden offline at Christmas

On 23/12/2017 I went to the Montana Ackermans store & bought items to the value of R3 528.50. When I handed the lady my club card so I could get the A.rewards, cause I was paying cash for the items, she quickly said that they were offline. Well I could pay for the items with my debit card & there was people around me that was buying items on their card (the accounts card & reward card, exactly the same card). Why would it be such an convenient time for them to be offline with the Rewards card, but I could use the same terminal to pay for the goods with my debit card. I want the purchase to be allocated to my Rewards card, because I spoke to one of the other cashiers at one of the other stores & she explained how this all works.