Holo script not Working? Changed

My holo script isnt working. I changed :GetRoleInGroup() to :GetRankInGroup to fix that problem but i found that there is something wrong with how the onChat function is called at the end of the script but i dont know what it is. Here's the updated script:

groupid=1209141
rankmin=10
open=false
hatchopen=false
first={}
success="Request completed"
notfound="Unable to complete request//Map Not Found"
notthere="Unable to complete request//Gamemode Does Not Exist"
gamemodes="ffa, teammatch"
maplist="hardobby, classic, paths"
lobby=math.random(-30.5,14.5),42.5,math.random(-969,-980)

function mode(mode,pr)
    if mode=="ffa" and open=true then
        teleport(arena)
    end
end

function success(per)
    local m=Instance.new("Message",per.Character)
    m.Text=success
    wait(1.5)
    m:Destroy()
end

function errr(err,pers)
    error(err)
    if err==notfound then
        local m=Instance.new("Message",pers.Character)
        m.Text=notfound
        wait(1.5)
        m.Text=("The current maps are:"..maplist)
        wait(2.5)
        m:Destroy()
    end

    if err==notthere then
        local m=Instance.new("Message",pers.Character)
        m.Text=notthere
        wait(1.5)
        m.Text=("The current gamemodes are:"..gamemodes)
        wait(2.5)
        m:Destroy()
    end
end

function loadmap(map,payer)
    local find=game.Workspace:FindFirstChild(map)
    if find~=nil then
        open=true
        find:Clone().Parent=game.Workspace.map
        wait(0.2)
        success(payer)
    end
    if find==nil then
        errr(notfound,payer)
        open=false
    end
end

function endmap(plr)
    local fd=game.Workspace.map:GetChildren()
    for i=1,#fd do

    end
end

function teleport(place)
    local plays=game.Players:GetPlayers()
    for i=1,#plays do
        plays[i].Torso.CFrame=CFrame.new(place)
    end
end

game.Players.ChildAdded:connect(function(player)
    function onChat(message,player)

        if message=="!end session" and player:GetRankInGroup(groupid)>=10 then
            local m=Instance.new("Message",game.Workspace)
            m.Text="Thank you for coming to "..first.."'s Training"
            game.Players:ClearAllChildren()
        end

        if message=="!start session" and player:GetRankInGroup(groupid)>=10 then
            teleport(lobby)
        end

        if message:sub(1,5)=="!load " and player:GetRankInGroup(groupid)>=10 then
            loadmap(message:sub(6),player)
        end

        if message:sub(1,4)=="!end " and player:GetRoleInGroup(groupid)>=10 then
            endmap(message:sub(5),player)
        end

        if message:sub(1,5)=="!mode " and player:GetRankInGroup(groupid)>=10 then
            mode(message:sub(6,player))
        end
    end
end)

game.Players.PlayerAdded:connect(function(player)
    player.Chatted:connect(function(message) onChat(message,player)
        if player:GetRankInGroup(groupid)>=10 and #first<1 then
            table.insert(first,player.Name)
            print("You're an admin")
        end
    end)
end)