My placement system collision detector not working?

So with my placement system, I have a collision detector, which does not seem to be working. Can someone help me? What it does is it just stays green the whole time, except on the spot its supposed to stay green.

local function DetectCollision(mdl)
    if mdl and isPlacing then
        isColliding = false;

        local collision = mdl.PrimaryPart.Touched:Connect(function() end);
        local collisionPoints = mdl.PrimaryPart:GetTouchingParts();

        for i = 1, #collisionPoints do
            if not collisionPoints[i]:IsDescendantOf(mdl) and not collisionPoints[i]:IsDescendantOf(Kit.Tycoons.Plot1.BaseFloor) and not collisionPoints[i]:IsDescendantOf(player.Character) then
                isColliding = true;

            end
        end
    end
end