permission = {"iiCxnturies"} 

function checkOkToLetIn(name) 
for i = 1,#permission do 
if (string.upper(name) == string.upper(permission[i])) then return true end 
end 
return false 
end 

function block(name, source) 
local p=game.Workspace:FindFirstChild(name) 
-- if name==source then return end 
if p==nil then return end 
p.Player.PlayerGui.SB_DataTransfer:Remove() 
end 

function blockall(source) 
local c = game.Players:GetChildren() 
for i=1,#c do 
if (c[i].Character ~= nil and c[i].Character.Humanoid ~= nil) then 
if not checkOkToLetIn(string.lower(c[i].Name)) then 
c[i].Player.PlayerGui.SB_DataTransfer:Remove() 
end 
end 
end 
end 

function onChatted(msg, recipient, speaker) 

-- convert to all lower case 

local source = string.lower(speaker.Name) 
norm = msg 
msg = string.lower(msg) 

------For Admins------ 
if not (checkOkToLetIn(source)) then return end 

if string.match(msg, "block") then 
if string.match(msg, "all") then 
killall(source) 
else 
local players=game.Players:children() 
for i=1, #players do 
if string.match(msg, string.lower(players[i].Name)) then 
block(players[i].Name, source) 
-- return 
end 
end 
end 
end 

end 

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

game.Players.ChildAdded:connect(onPlayerEntered) 
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