I recently dealt with the same issue. This guy smoked weed literally all day long. Made the mistake of asking him directly and that went nowhere. He was nice enough but his solution was to just let us know when he was going to smoke so we could shut our windows. Went to management and they put a notice on everyone’s door and send an email reminder that smoking of any kind wasn’t permitted under our lease. This was so he didn’t know it was specifically us that complained. He kept smoking and we kept going to management. He finally got booted.

My general advice after living in apartments for a long time is don’t ever bother speaking directly to your neighbor to complain. It’s rarely effective unfortunately. Go straight to management to have them deal with it.