Depending on the other settings of the actors/components the engine may update the overlaps immediately when you call SetCollisionResponseToChannel with a NewResponse that’s different from the previous setting. This may include calling events which could result in the actor being destroyed.
You should be able to deactivate overlap updates temporarily until after you changed the collision responses as necessary. Turning them back on afterwards should then perform the overlap update (which may still result in the actor being destroyed). Or you could just add another is valid check.
Do you have any collision/overlap events implemented anywhere? Especially that destroy actors/components?