I work at an electricity company managing accounts. A woman calls up about an electrity bill she just recieved and blasts me. "I paid $150 onto this account, I don't any more money, you bastards can go fuck yourselves, I'm not paying this bill!" she screams.
"Uh... can you read me the account number on that bill?" I ask.
She reads me off an account number and sure enough, there's $40 owing. The financial history shows that no money has EVER been paid onto this account.
"We never recieved that $150... infact, we've never recieved any payments on this account." I explain.
"Goddamnit, I paid the money in cash at the post office and if you idiots never recieved it then it's not my damned problem."
"...do you have a receipt there for the payment?" I ask.
"Yep, I kept it, it's right here."
"Can you read me out the account number on the receipt?"
She then proceeds to read me out a COMPLETELY DIFFERENT ACCOUNT NUMBER. With both pieces of paper side by side, she needs me to point out that the numbers are different.
Her brilliant comeback?
"It doesn't matter that the numbers are different, what matters is that you lost my money!"