Zero knowledge from cashier about virtual cards

I went in the store at N1 City to purchase and wanted to have a lost card replaced- I was told that I will have to call a number, I was not given the number to call and had to ask the cashier for it. I asked her if there was no other way since I have the App on my foun and she said no- She still expected that I pay for the items, but how? since I do not have the card?? I ended up leaving without the items- only to find out later when I went on the App that I can use the virtual card on the App. Pathetic service if you ask me.