I only had a $20 bill.....and then I found 50 cents. Gave it both to the girl. She stared....looked at the cash register, rubbed the coins together, held the banknote, stared some more and then she called the supervisor, and the dear girl stared the same way: vacant.
Then I lost it and took the 50 cents back, assuming from there on it would be easy. Not so. I had to figure it out for her.
Welcome to the tech world. Maybe it's time we start using our brains again.