The text will change once you login.. using /login command
Do /debugscript 3 and post the errors here.
You can change the server side to:
addCommandHandler ("acc",
function (p)
local account = getPlayerAccount (p)
local accountName = getAccountName (account)
triggerClientEvent ('handleClient',source,accountName)
end
)
After you change it, have the GUI opened, and do /acc it should work, if it didn't, post /debugscript 3