Raid gets stuck in the middle but the boss bar is still there.

I was fighting off a raid when on one wave, it said there was 1 raid mob left but I was looking for it everywhere and I couldn't find it. Then I went in creative to find it and I still couldn't find it. I tried following the iron golems but they weren't going anywhere. I could still hear the raid noises though. (The ones that go like "huh-huh-hu-hunnnng")

Steps to reproduce:

1. Start a raid. You can give yourself bad omen with /effect @s bad_omen [seconds]
2. You need to kill a few pillagers. I usually get it stuck at wave 1 or 2.

Expected result: When you kill all the pillagers on a wave it will go to the next wave.

Observed result: The raid bar gets stuck at 1 raider remaining when there are no pillagers left.