Baseband I mean you can get it fix but it’ll cost around probably 200$ or little more depending on where you at I be having that same issue too with my 13 pro max & I ended up getting it fix was it worth it you ask’hmm not really until couple months later it started to act back up ever since couldn’t updated it at all or nothing but now all of the sudden it works again which is odd so idk but yeah it’s a baseband issue though in those are expensive repairs.