Wondering how to handle this situation on grindr (encountering someone you used to know)

I know not to expect much from grindr, but I was curious what you all thought of my situation and if you had any suggestions on how to handle it.So there's this guy that I used to go to middle school with. We weren't like best friends or anything, but we were friendly with each other. I remember sitting next to him, and talking and laughing together about a lot of stuff. I'm not sure if he moved away or what, but I basically haven't seen him since middle school since we haven't really kept in touch.Fast-forward like over a decade, and I see his profile on grindr. He's grown up really well lol, barely recognizable. But after contemplating, I decide to message him. I don't make any mention of knowing who he is, so that I don't creep him out or anything. Interestingly enough, he responds asking if I am who I am and that he used to know me in middle school and we had a class together, etc (in a very surprised, enthusiastic, friendly way). So I kinda go with it, and we exchange a couple messages about how long it's been and all of that. It was a very friendly exchange.However, after that, he completely stops responding. It's been almost 2 weeks since he last replied, and I'm not really sure why. This happened around the time of the grindr outage where they were saying the messages didn't work, so I thought it might be that. But after it was supposedly resolved, I tried messaging him again just to see how he was doing, and still no response.I'm pretty confused about this, and kinda disappointed, cuz I was actually genuinely interested in him, even if just for the friendship. I just don't understand why he would've responded in the first place if he wasn't interested, let alone make mention of how we used to know each other. I'm trying to imagine the situation from his perspective, and I don't get it. If you received a message from someone you used to know and recognized them, but weren't interested in them at all, why would you bother responding and make a big deal about how we know each other?? Why not just ignore me? I guess I'd get over it if it was just a random guy I didn't know, but the fact that we do know each other makes it kinda weird.. It's not like we hated each other back then.Just curious what you all think.. Is this normal behavior? Should I try to message him again? Friend request him on Facebook? (lol just kidding, i'm not that crazy). Anyway, sorry for the long post!! Thanks for any advice!