Smart Shopper Points and Store Account cannot be used for one transaction

I visited Pick `n Pay Oakfields in Northmead, Benoni on 2018-02-16 to buy a few things as i approached the till I presented my smart shopper card as well as the slip which indicates my switched points balance she used the points and I wanted to pay for the balance with my store account I was informed that this was not possible. WHY??? My smart shopper points and store account HAVE NOTHING TO DO WITH EACH OTHER. The staff were terrible and just shrugged their shoulders I am highly disgusted and will NEVER visit the store again.