If you reload the world during the raid, the raid's boss bar will disappear. If the command kills the illagers from the first wave, the second one will not appear. Reproduce:
Create an artificial village with a villager and a bed and drink an ominous bottle or use the command /effect give @s minecraft:raid_omen to start a raid.
After the first wave of illagers appear, reload the world.
After that, the raid's boss bar will disappear and the illagers will stop running around looking for villagers.
Use the /kill @e[type=#raiders] command. A new wave of illagers will not appear.
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