What would you say?

Sorry if this sounds ridiculous/ A guy I was only acquaintances with and rarely spoke to messaged me. After months of no communication he sent me “hey beautiful” at like 10:30pm but I was sleeping and didn’t see it until 9:30am. I thought it was really weird and didn’t say anything but I also didn’t want to just leave him on read since everything prior to that was just random things in passing and I feel like it’d be mean. I’ve been thinking about it all day. I just don’t like him beyond friends. What would you say?