In Need Of A Four-Letter Word

Customer: “I forgot my account number; can you look it up?”

Me: “Sure. Just tell me how to spell your last name.”

Customer: *gives me a five-letter name*

Me: “I’m sorry; it’s not working. Are you sure it’s spelled [spells out loud]?”

Customer: “Yes, that’s right.”

Me: “I’m sorry; still nothing’s coming up. Are you certain you have an account here?”

Customer: “Yes, I just made a deposit yesterday!”

Me: “I’m sure it’s just something simple; perhaps I’ve spelled your name wrong. Can I see your ID?”

(The customer hands me their ID, at which point I see that the last name is nine letters long.)

Me: “You’ve only been giving me the first five letters of your last name.”

Customer: “What, you need my whole name?”