Why does he do this?

There’s this one guy who’s my friend. We’ve had a past recently but I thought things were going okay recently. For the past few weeks I’ve been posting insta pics and he’s liked mostly all of them, something he didn’t do after recent events. The last one he liked was a few days ago. I sent him a meme last night (something we’ve always done) and he liked it. I even posted on my story after I posted my pic today and he saw it. But he still hasn’t liked my pic and it’s been like 6 hours. He’s done this before though where he won’t like it until hours later. I know it’s just social media and it doesn’t matter but this is the only way of “communicating” with him cause he lives far away. It just kinda gives me mixed feelings because I don’t wanna lose him as a friend. Maybe he just hasn’t seen it bc instas algorithm?