+1 to both the above. It happens. Don’t minimize it, own the mistake, and turn it around to a positive. By that, I mean to demonstrate how you know never to let your guard down even if experienced, and that it has made you a better pilot because _____.
If I’m understanding you right, this just happened, after your interview was scheduled. Do NOT succumb to the temptation to gloss over it when they ask you to add to/change your app and to sign it. Bring it up. How you frame it will determine your fate, but don’t be nervous or it will show. Be humble about it, and you should be fine.