How does he know it’s me?

I closed an account after adding a guy that admits he’s the guy I know in person. Meanwhile, I opened a new account under my middle name; a way of being more anonymous and the same guy found me and added me as before. He doesn’t know my middle name. How did he know it was me? I did ask similar questions on my last account that I closed and I’ve mentioned the country I’m from.

How does he know it’s me?
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