Did you tear/take out all the coop interior including bedding, nestboxes, feeders, water dispensers and the roosts for cleaning?
It is best to clean everything far away from the coop using a tarp underneath, so the mites cannot escape and instantly run back.
Don't forget to spray the ceiling of your coop and the exterior coopwalls including the roof as well. The underside in case it is a raised coop and underneath the roof tarp or shingles, even the exterior chicken ladder needs to be treated.
Prior to spraying, I would use a bunsen burner to carefully flame every nook and cranny (flaming mites causes a crackeling sound) but always keep a bucket filled with water handy, in case you set the coop on fire.
Maybe think of letting your chickens stay somewhere else far away from their usual coop and run for as long as it takes to get everything mite free.
But make sure they are mite free and will not spread the infestation.