falsely accused of ai

i’m a senior in high school applying to colleges (so nothing can go on my record), and i just got accused of using ai by my english teacher. this was on our first take-home essay (all others have been in class and timed). obviously, i know my writing style is different and better when i’m not under time constraints, which i think is part of why i got accused.

i’ve run my essay through multiple ai checkers and the highest i got was 20%, so nothing crazy. the essay is also a blend of narrative and literary analysis so it has a ton of personal stories, which i think would be hard to use ai for so i really don’t get the accusation. this is the teacher’s email:

“Dear student, You are receiving this email because your Personal Connections Analysis Essay scored a significantly high percentage of AI use. Due to the significant amount of unreliable of authentic work, we will be completing a re-write assignment in class Tuesday. More information will be explained in class. Also, please note you may be called into the Dean’s office this week regarding the assignment.”

i’m irritated by the rewrite, but my main concern is the dean’s office. i’m terrified they’ll accuse me of cheating and i don’t know how to prove i didn’t. my teacher has access to the history (which shows i worked on it over many days and different times). i’m planning to email my teacher to offer other outside-of-class assignments from previous years to show her this is my true writing style.

if i do get called into the dean’s office, what can i say? how can i prove i didn’t use ai without it looking like i’m defensive? it’s crucial nothing goes on my record. please help!