If someone claims an incident I don't remember, what do I reply?

Someone texted me just minutes ago on my FB messenger. The woman claims my friends and I invited her to a party but that I gave her a false number and fake address and that I said ''You need a make-over'' in 9th grade.

This doesn't ring a bell to me. I really don't remember being mean to anyone so I'm taken aback by that claim. My reply was a Really? I did? She said yes (my name), you did.

My HS was large and new people kept filling the classes each year. I had my own group of friends and didn't speak to half the class so some things are a blur to me. The woman's name sounds familiar and I think I had her in one class but that's it. I don't recall anything else. What do I proceed with this claim I have no recollection of?

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+1 y
I can't stop thinking about that claim. I just don't remember that incident she's referring to. I have no problems admitting when I'm wrong but how can I reply to something I don't recall. What she's saying doesn't ring a bell to me.
If someone claims an incident I don't remember, what do I reply?
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