Have you ever met a terrible shopkeeper?

After eating, I asked the waiter to pay the bill. The waiter asked me to go to the counter. After going to the counter, I threw a seven-dollar bill directly and was ready to go. Then I was stopped. The cashier said the five-dollar bill was broken. I took it and saw that it really broke a corner. Then I quickly handed another twenty. After handing it in, she said it was broken and the bank wouldn't accept it. Now I am stupid. Twenty is a brand new one. How did it break another corner? Now I can be sure that this is definitely not broken. Unexpectedly, after she took it, she looked at the authenticity and handed it to me, saying that this was also broken. On closer inspection, a corner disappeared directly. She also said that you don't have a brand-new hundred.