Random friends already in DMS

I have several people on my friend list whom I don't know at all. We have no friends or servers in common, and no conversation history at all. I've DMed them all, asking if they remember how we became friends and they all said that they did not remember friending or talking to me at all. Does anyone know why this is happening? I only friend people on Discord whom I know in person or if we've chatted a lot before. Thank you :)

Here's one of the chats.