Someone else's name on my Apple Notes???

I was looking at who made edits on a shared Apple note that is only shared between me and my girlfriend. However, I see that the name responsible for my edits is "Jennifer" (not my name nor my girlfriend's). I checked my settings and my Apple ID is the only one signed into my phone, and my phone and laptop are the only two devices that have my Apple ID signed in. My own name is still the one on my Apple ID and not "Jennifer", so it can't be that my name was changed. My real name also appears as responsible for edits on other notes that I have so it's just that specific shared note that's the problem. I'm an overthinker so my mind just assumed the worst that I've been hacked but I'm not sure if I'm being paranoid lol. What are some explanations for this, and how should I go about solving it?