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: happened about 30 mins ago. 
i was at my orthodontists and was walking out when i remembered that i forgot to pay. went up and asked to pay, they hadn't even put in an invoice for my visit. i could have just walked out free of charge and nobody would have noticed. 275$ later at least i have some peace of mind...

TIFU getting a free retainer