My best buddy ghosted me out of the blue

I (33m) have been best friends with a guy (32m) since I was 17. Over 15 years. For a little backstory, we started hanging out, smoking and gaming, and within a few months become pretty inseparable. I've moved away from our hometown a few different times, but we always stayed in contact. In our mid 20s, we even lived together for a bit. We've never had a big argument, just little times that we both get a little annoyed with the other. No big deal, a day later we're playing games again. Since 2019, we've lived ~1 hour apart, played games online almost every night, and make each others' sides split from laughter.

A few months ago in Jan, we were trading TikToks when he stopped replying. A week goes by and I figure he forgot to reply (happens to us all) or got busy. No biggie. Then it's 2 weeks, then 3, and then I start to worry. What did I say? I don't remember being rude or a jerk, at least no more than we both playfully are with each other. I ask about it. No reply. Now it's mid-Feb and I send a long text, asking what was up, telling how I feel, letting him know I'm still here if he needs me. I even tried to get his baby mama to ask him, but he just told her to mind her business. Like, wtf is going on?!? I don't think he's blocked me either, because my calls still go through. I still send him random texts and calls just to see if maybe he'll pick up, and so he knows I ain't forget about him.

I dunno what to do. This dude is my brother, we were close with each others' families. I don't wanna lose that.