cannot buy because there is no change

i went to pep church street and bosman in Pretoria , round about 16: 50, the lady by the name Kgothatso couldn't assist me because they don't have a change I asked her, so does that mean I must not buy,, she said yes , I told her i'm not there to ask for a change m there to buy, I ended up leaving the store I was very disappointed because this was the nearest place I could buy the item

please help!