Just saying sometimes when a person thinks they’re correct, it helps to go through it step-by-step.
Usually, it helps.
I paid for a sandwich with a $10.00 bill and was given $14.00.
It was not my place to go through the register with the girl and explain how to take money and give change.
I brought it to the attention of the manager and let him deal with it.
Your point applies to the manager and the clerk but not me and the clerk.