Direct message issue

I’m trying to direct message someone who responded to a question I had. WHen I click on “message”

from his page, the message window opens but it doesn’t have that person listed and instead has some woman who I have never messaged before. the person I’m trying to message is labelled andrew and the person that shows up in my direct message box is labelled Jenny. I would still like to message andrew but I guess i’ll try through LI. thanks