My boss came to me today and said," the night you and A---- closed together, the alarm went off 5 after 10 when I received the call. When I came in, I noticed the food bar was poorly cleaned, and the back kitchen floor was not swept at all, so you need to step up with your performance." She is wrongfully accusing me of poorly cleaning and setting the alarm off because my coworker, C----, mentioned how he accidentally set the alarm off a few days after A---- and I closed. Note that he is known for poor cleaning. I have my clock out skip that states the night A----- and I closed, I left at 10:32pm, and not around 10:05pm. So should I write my boss a letter of confrontation with my evidence, or just let it go?