Why isn't mouse.hit.p working?

So I wanted to do a script in which I would spawn a sphere where the player is, and it would take damage and hold them in that Sphere for eight seconds. But It's not working.

local Player = script.Parent.Parent
local mouse = Player:GetMouse()
function YamiCage()
	if mouse.Hit ~= nil then
		S = Instance.new("Part")
		S.BrickColor = BrickColor.new("Really black")
		S.Transparency = 0.5
SM	=	Instance.new("SpecialMesh")
		S = SM.Parent
		SM.MeshType = "Sphere"
		SM.Scale = Vector3.new(1.1, 1.5, 1.5)
		S.CFrame = CFrame.new(mouse.Hit.p)
		local human =  S:FindFirstChild("Humanoid")
		if(human ~= nil) then
			Humanoid.Health = Health - 2
		end
		game:GetService("Debris"):AddItem(S, 8)
	end
end
mouse.Button1Down:connect(YamiCage)

I need some answers :c

You need gave the part a parent so it defaults to nil meaning it doesn't render. You also tried redefined your S variable to the mesh's parent to nil because you never assigned a parent to the mesh. Meshes need to be assigned to a child of the part. I'll add comments and put the part in Workspace and put the mesh in the part.

local Player = script.Parent.Parent
local mouse = Player:GetMouse()
function YamiCage()
    if mouse.Hit ~= nil then
        S = Instance.new("Part", Workspace) --I put the part in the Workspace
        S.BrickColor = BrickColor.new("Really black")
        S.Transparency = 0.5
SM  =   Instance.new("SpecialMesh")
        SM.Parent = S --Changed SM's Parent to the part created earlier
        SM.MeshType = "Sphere"
        SM.Scale = Vector3.new(1.1, 1.5, 1.5)
        S.CFrame = CFrame.new(mouse.Hit.p)
        local human =  S:FindFirstChild("Humanoid")
        if(human ~= nil) then
            Humanoid.Health = Health - 2
        end
        game:GetService("Debris"):AddItem(S, 8)
    end
end
mouse.Button1Down:connect(YamiCage)