How to use / as a keybyte?

I am making a custom chat, which uses the same thing as kinda like roblox's chat but I disabled the coregui for chat. This works in studio but doesnt work in player so It must be something to do with the keybyte() == 47 anyone know how to enable it?

local player = game.Players.LocalPlayer
local mouse = player:GetMouse()
local able = false
local default = script.Default

function onkey(key)
	if key:byte() == 47
		then
		script.Parent:TweenSizeAndPosition(UDim2.new(1,0,.05,0), UDim2.new(0,0,.45,0), "Out", "Quad", .5, true)
		script.Parent.TextXAlignment = "Center"
		script.Parent:CaptureFocus()
		able = true
	end
end

function clear()
	script.Parent:TweenSizeAndPosition(UDim2.new(1,0,.025,0), UDim2.new(0,0,.975,0), "Out", "Quad", .5, true)
	script.Parent.TextXAlignment = "Left"
	able = false
	script.Parent.Text = default.Value
end

mouse.KeyDown:connect(onkey)
script.Parent.FocusLost:connect(clear)