Definition: In this task, you are given a Reddit post as a text. Your task is to generate a title for this text. The title should start with "TIFU by", followed by a situation that caused humor. The title should contain 7-12 words, ideally.
Input: Text: not world ending, but i needed to get this off my chest.

the fuck up happened a week ago, but i only discovered it today. some guy bid on an auction for a videogame cart and despite repeated messages from me never paid. so i give up and relist the item which sells for about half the original price (£30 or $40)

i go the the ebay seller dashboard and get the name of where to send it and off it goes. a week later the second guy asks where his cart is. i check and the post office say it's been delivered. so i check again and realise that because ebay leave failed and successful auction next to each other -and i'm an idiot- i clicked the wrong listing and sent it to the wrong guy.

so now he not only bilked me on the first auction, he gets the  cart for free.

TIFU by sending the Non-Paying eBayer the item instead of the guy that bought re-listed item.