Trying to use collectionservice to change humanoid health of tagged enemies?

I have this script, no errors in output but its not seeming to work. i have a part the spawns and if the player touches it, i want all the enemies tagged "Zombie" to have there health set to 1. heres the script

wait(1)
function onTouched(part)

    if part.Parent.Name == "Zombie" then
        game.Workspace["power ups"].NT:Play()
    else
        if part.Parent:findFirstChild("Humanoid") then
            game.Workspace["power ups"].IK:Play()
            script.Parent.Position = Vector3.new(0, -50, 0)
            local CS = game:GetService("CollectionService")
            local temp = CS:GetTagged("Zombie")
            for i in pairs(temp) do
                local ZomHum = temp[i]:FindFirstChild("Humanoid")
                ZomHum.Health = 1

            wait(30)

            end
        end
    end
end 
script.Parent.Touched:connect(onTouched)