UserInputService does not detect input?

I've made a script that detects when a specific key is pressed. I have tried putting a print function to see if it was detected or not and it did not print the message. Could it be something to do with studio?

Script:

local uis = game:GetService("UserInputService")
local plr = game.Players.LocalPlayer
local chatting = false
local frame = script.Parent

plr.Chatted:connect(function(msg)
    chatting = false
end)

uis.InputBegan:connect(function(input)
    if input == Enum.KeyCode.Slash and game.StarterGui:GetCoreGuiEnabled("Chat") then
        chatting = true
    elseif input == Enum.KeyCode.Return then
        chatting = false
    end

    if chatting == false then       
        if input == Enum.KeyCode.Equals then 
        frame.Visible = not frame.Visible
        end
    end
end)

I am using a localscript btw