Bad service at till

Hello, was at dischem in canal walk today and when my wife asked the cashier whos nametag displays the name pretty at till 15 if she could please check the amount available on our dischem loyalty card , to obviously use the available funds, she told my wife no and she has to check the points at the entrance counter . when i asked two other employees in the store i was told the cashier can see the amount available when the card is swiped, one employee even checked it at one of the cashier tills and showed me the available funds on the card, yet this cashier named pretty told us she cant do it. Please let me knw what exactly we are supposed to do when whe want to use the funds on these loyalty cards , or was this perhaps just an employee with a bad attitude who does not care about customer satisfaction.