Here's the thing. Chickens will often prefer to sleep in a comfy nest box even when the perches are higher than the nests. You can try all sorts of tricks to try to get them to stop, but the only way you'll succeed is to block off the nests at night, and be prepared to block them off each night for a good long while.
I have two coops and sets of nest boxes in each. The perches are higher than the nests. Yet, there are a few hens that try to sneak into the nests whenever they can.
One of these hens routinely roosts in one coop, yet each night she goes to the other coop and checks to see if I've forgotten to block off the nest boxes. If I'm absent minded, she will immediately take possession of a nest at floor level and snuggle in for the night. That is, until I notice and swat her butt out of the nest with a broom. Undeterred, she continues to routinely check the coop each night for an unblocked nest.
I have no illusions of ever training her to stop opportunistically trying to catch me absent minded. To combat these hens' bad habits, I've developed my own habit of blocking the nests off each night. It's easier than fighting with the stubborn critters.