The Broken Phone

Customer: My new phone isn't working. The screen is blank.

Assistant: Is it charging? What's the battery doing?

Customer: I'm clicking the button, but nothing's happening. The screen stays black.

Assistant: Can I see it?

(The customer hands over the phone. The assistant turns it over.)

Assistant: Sir, this is a calculator.

Customer: Oh. Is that why it won't accept my password?

Assistant: That's because it doesn't have one. It's a calculator.

Customer: So can you fix the battery?

Assistant: I can sell you a phone.