Certain Player Chatted Function?

I've recently tried to make a script where it only runs when a certain player(s) say something in the chat. When the script runs the scripts Parent or the "door" will open. The script will have two functions so when the player(s) say "StoreOpen" it opens and when the players say "StoreClose" it closes.

what my trashy self came up with

door = script.Parent 

function onChatted(msg, recipient, speaker) 
local source = string.lower(speaker.Name) 
msg = string.lower(msg) 

if (msg == "open") then 
door.CanCollide = false 
door.Transparency = 0.7 
wait(5) 
door.CanCollide = true 
door.Transparency = 0 
end 

end 

function onPlayerEntered(newPlayer) 
newPlayer.Chatted:connect(function(msg, recipient) onChatted(msg, recipient, newPlayer) end) 
end 

game.Players.ChildAdded:connect(onPlayerEntered)